Future of weather and climate forecasting - WMO Open Consultative Platform White Paper #1 - WMO Library

Page created by Danielle Alexander
 
CONTINUE READING
Future of weather and climate forecasting - WMO Open Consultative Platform White Paper #1 - WMO Library
WEATHER CLIMATE WATER

                                       Public-Private Engagement Publication No. 3

       WMO Open Consultative Platform White Paper #1
                       Future of weather and
                          climate forecasting
WMO-No. 1263
Future of weather and climate forecasting - WMO Open Consultative Platform White Paper #1 - WMO Library
Cover photo credits:
© iStock

© World Meteorological Organization, 2021
The right of publication in print, electronic and any other form and in any language is reserved by WMO. Short extracts
from WMO publications may be reproduced without authorization, provided that the complete source is clearly indicated.
Editorial correspondence and requests to publish, reproduce or translate this publication in part or in whole should
be addressed to:

Chairperson, Publications Board
World Meteorological Organization (WMO)
7 bis, avenue de la Paix
P.O. Box 2300
CH-1211 Geneva 2, Switzerland

Tel.: +41 (0) 22 730 84 03
Fax: +41 (0) 22 730 81 17
Email: publications@wmo.int

ISBN 978-92-63-11263-7

NOTE
The designations employed in WMO publications and the presentation of material in this publication do not imply the expression of
any opinion whatsoever on the part of WMO concerning the legal status of any country, territory, city or area, or of its authorities, or
concerning the delimitation of its frontiers or boundaries.

The mention of specific companies or products does not imply that they are endorsed or recommended by WMO in preference to others
of a similar nature which are not mentioned or advertised.

The findings, interpretations and conclusions expressed in WMO publications with named authors are those of the authors alone and do not
necessarily reflect those of WMO or its Members.
Future of weather and climate forecasting - WMO Open Consultative Platform White Paper #1 - WMO Library
WEATHER CLIMATE WATER

                                       Public-Private Engagement Publication No. 3

       WMO Open Consultative Platform White Paper #1
                       Future of weather and
                          climate forecasting

WMO-No. 1263

                                                                                     i
Future of weather and climate forecasting - WMO Open Consultative Platform White Paper #1 - WMO Library
CONTENTS

     FOREWORD. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .  V

     ACKNOWLEDGEMENTS. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1

     1. INTRODUCTION. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3

          1.1 The need for a vision for climate forecasting and weather prediction. . . . . . . . . . . . . . . . . . 3
          1.2 Objective and scope of this White Paper. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4

     2. WEATHER AND CLIMATE FORECASTING: SETTING THE SCENE . . . . . . . . . . . . . . . . . . . . . . . . . 6

          2.1 Brief history. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
          2.2 WMO coordination role. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
          2.3 Baseline 2020. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11

     3. CHALLENGES AND OPPORTUNITIES IN THE COMING DECADE. . . . . . . . . . . . . . . . . . . . . . . . . 12

          3.1 Infrastructure for forecasting. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
                3.1.1 Observational ecosystem. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
                3.1.2 High-performance computing ecosystem. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
                3.1.3 Changing landscape: advances in infrastructure through
                public–private engagement. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15

          3.2 Science and technology driving advancement of numerical prediction . . . . . . . . . . . . . . . 16
                3.2.1 Evolution of numerical Earth-system and weather-to-climate prediction . . . . . . . . . 17
                3.2.2 High-resolution global ensembles. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19
                3.2.3 Quality and diversity of models. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19
                3.2.4 Innovation through artificial intelligence and machine learning . . . . . . . . . . . . . . . . 19
                3.2.5 Advancing together: leveraging through public–private engagement. . . . . . . . . . . . 20

ii
Future of weather and climate forecasting - WMO Open Consultative Platform White Paper #1 - WMO Library
3.3 Operational forecasting: from global to local and urban prediction . . . . . . . . . . . . . . . . . . 21
           3.3.1 Computational challenges and cloud technology . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22
           3.3.2 Verification and quality assurance. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23
           3.3.3 Further automation of post-processing systems and the evolving role
           of human forecasters. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24
           3.3.4 Leveraging through public–private engagement. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25

     3.4 Acquiring value through weather and climate services. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25
           3.4.1 User perspective. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26
           3.4.2 Forecasts for decision support. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26
           3.4.3 Bridging between high-impact weather and climate services . . . . . . . . . . . . . . . . . . 26
           3.4.4 Education and training for future operational meteorologists/forecasters. . . . . . . . 27

4. CONCLUSIONS. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28

     4.1 Towards improved systems for forecasting: global, regional and local approaches. . . . . . 28
     4.2 Progressing together with developing countries. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30

REFERENCES. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32

BIBLIOGRAPHY . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33

                                                                                                                                                         iii
Future of weather and climate forecasting - WMO Open Consultative Platform White Paper #1 - WMO Library
© iStock

     Amazing supercell in Colorado

iv
Future of weather and climate forecasting - WMO Open Consultative Platform White Paper #1 - WMO Library
FOREWORD
The advancement of our ability to predict                      This White Paper on the Future of Weather and Climate
the weather and climate has been the core                      Forecasting is a collective endeavour of more than
aspiration of a global community of scientists                 30 lead scientists and experts to analyse trends,
and practitioners, in the almost 150 years                     challenges and opportunities in a very dynamic
of international cooperation in meteorology                    environment. The main purpose of the paper is to
and related Earth system sciences.                             set directions and recommendations for scheduled
                                                               progress, avoiding potential disruptions and leveraging
The demand for weather and climate forecast                    opportunities through public–private engagement over
information in support of critical decision-making             the coming decade. This is done through description
has grown rapidly during the last decade, and                  of three overarching components of the innovation
will grow even faster in the coming years. Great               cycle: infrastructure, research and development, and
advances have been made in the utilization of                  operation. The paper presents the converging views of
predictions in many areas of human activities.                 the contributors, but also accounts for some variations
Nevertheless, further improvements in accuracy                 of those views in areas where different options exist for
and precision, higher spatial and temporal                     advancing our capacity to predict weather and climate.
resolution, and better description of uncertainty              Thus, it informs and provides for intelligent choices
are needed for realizing the full potential of                 based on local circumstances and resources.
forecasts as enablers of a new level of weather-
and climate-informed decision-making.                          I am pleased to present the White Paper on the Future
                                                               of Weather and Climate Forecasting to the global
                                                               audience and to encourage the use of its findings and
In June 2019, WMO launched the Open Consultative               recommendations by decision makers, practitioners and
Platform (OCP), Partnership and Innovation for the             scientists from all sectors of the weather and climate
Next Generation of Weather and Climate Intelligence,           enterprise. I would like to acknowledge, with much
in recognition that the progress in weather and climate        appreciation, the work done by Dr Gilbert Brunet, Chair
services to the society will require a community-wide          of the WMO Scientific Advisory Panel, as the lead author
approach with participation of the stakeholders from           and coordinator of the group of more than 30 prominent
the public and private sectors, as well as academia and        scientists and experts worldwide who contributed to the
civil society. The OCP is expected to serve as a vehicle for   paper. I would like also to express my sincere thanks to
sustainable and constructive dialogue among sectors,           all the contributing authors and reviewers for devoting
to help articulate a common vision for the future of the       their time and sharing their knowledge and foresight for
weather and climate enterprise in the coming decade            the benefit of the whole enterprise.
and beyond.

Undoubtedly, the 2020s will bring significant changes
to the weather, climate and water community: on the
one hand through rapid advancement of science and
technology, and on the other hand through a swiftly                               Prof. Petteri Taalas
changing landscape of stakeholders with evolving                                  Secretary-General
capabilities and roles. Such changes will affect the
way weather and climate forecasts are produced and
used. This is the reason the OCP selected the theme
of “Forecasting and forecasters” as one of the “grand
challenges” of the coming decade, which will require
collective analytics to identify opportunities and risks
and provide advice to planners and decision makers of
relevant stakeholder organizations.

                                                                                                                           v
Future of weather and climate forecasting - WMO Open Consultative Platform White Paper #1 - WMO Library
ACKNOWLEDGEMENTS
    This paper has been prepared by a drafting team led by Gilbert Brunet, Chief Scientist and Group Executive
    Science and Innovation, Bureau of Meteorology, Chair of the Science Advisory Panel, World Meteorological
    Organization.

    The team of contributing authors includes (in alphabetical order):

    Peter Bauer                        Deputy Director, Research Department, European Centre for Medium-Range
                                       Weather Forecasts

    Natacha Bernier                    Director, Meteorological Research Division, Environment and Climate Change
                                       Canada

    Veronique Bouchet                  Acting Director General, Canadian Centre for Meteorological and Environmental
                                       Prediction, Meteorological Service of Canada, Environment and Climate Change
                                       Canada

    Andy Brown                         Director of Research, European Centre for Medium-Range Weather Forecasts

    Antonio Busalacchi                 President, University Corporation for Atmospheric Research, USA

    Georgina Campbell                  Executive Director, ClimaCell.org; CSO and Co-Founder, ClimaCell
    & Rei Goffer

    Paul Davies                        Principal Fellow of Meteorology and Chief Meteorologist, Met Office, UK

    Beth Ebert                         Senior Professional Research Scientist, Weather and Environmental Prediction,
                                       Bureau of Meteorology, Australia

    Karl Gutbrod                       CEO, Meteoblue, Switzerland

    Songyou Hong                       Fellow, Korean Academy of Science and Technology, Republic of Korea

    PK Kenabatho                       Associate Professor, Department of Environmental Science, University
                                       of Botswana, Botswana

    Hans-Joachim Koppert               Director, Business Area “Weather Forecasting Services”, Deutscher Wetterdienst,
                                       Germany

    David Lesolle                      Lecturer (Climatologist), Department of Environmental Science, University
                                       of Botswana, Botswana

    Amanda Lynch                       Lindemann Professor, Institute for Environment and Society, Department of Earth,
                                       Environmental and Planetary Sciences, Brown University, USA

    Jean-François Mahfouf              Ingénieur Général des Ponts, Eaux et des Forêts, Météo-France, Toulouse, France

    Laban Ogallo*                      Professor, University of Nairobi, Kenya

    * The contributors to this White Paper express their great sadness of the demise of Prof. Laban A. Ogallo who passed away in November 2020. Prof.
    Ogallo was one of the pioneers of climate science in Africa and he provided a significant input to the White Paper.

1
Future of weather and climate forecasting - WMO Open Consultative Platform White Paper #1 - WMO Library
Tim Palmer             Royal Society Research Professor of Climate Physics, Professorial Fellow,
                       Jesus College Oxford, UK

David Parsons          President’s Associates Presidential Professor, Director Emeritus, School
                       of Meteorology, University of Oklahoma, USA

Kevin Petty            Director, Science and Forecast Operations and Public-Private Partnerships,
                       The Weather Company, an IBM Business

Dennis Schulze         Managing Director, MeteoIQ, Chairman of PRIMET, Chairman of Verband Deutscher
                       Wetterdienstleister e.V. (VDW)

Ted Shepherd           Grantham Professor of Climate Science, University of Reading, UK

Thomas Stocker         Professor, Head of Division Climate and Environmental Physics, Physics Institute,
                       University of Bern, Switzerland; President of the Oeschger Centre for Climate
                       Change Research, Switzerland

Alan Thorpe            Visiting Professor, University of Reading, UK

Rucong Yu              Deputy Administrator, China Meteorological Administration

The group of reviewers who provided valuable comments and proposals for improving the narrative
of the paper included:

V Balaji               Head, Modeling Systems Group, Princeton University, USA

Brian Day              Vice-President, Campbell Scientific, Canada

Andrew Eccleston       General Secretary, PRIMET

Roger Pulwarty         Physical Scientist at National Oceanic and Atmospheric Administration, USA

Julia Slingo           Retired, former Chief Scientist of the UK Met Office (2009-2016)

The work of the drafting team was supported by Dimitar Ivanov and Boram Lee from the Secretariat
of the World Meteorological Organization.

                                                                                                           2
Future of weather and climate forecasting - WMO Open Consultative Platform White Paper #1 - WMO Library
1. INTRODUCTION

                                                                                   forecasts provide major support for life-saving decisions
    1.1 The need for a vision for weather                                          through mitigation of the risk of weather and climate
    and climate forecasting                                                        hazards. In addition, improved forecasts create tangible
                                                                                   socioeconomic benefits in many economic sectors (for
    Weather and climate forecasting is a leading                                   example, energy, transport and agriculture), through
    environmental and socioeconomic challenge                                      avoided losses, better management of resources and
    – whether on an urban or planetary scale, or                                   enhanced opportunities for revenue.
    covering a few hours or a few seasons. Significant
    progress has been achieved in numerical Earth-                                 Policy debates around the future of the planet and
    system1 and weather-to-climate prediction                                      society are intense in a world with significant global
    (NEWP) over the past six decades, through                                      technological transformations and environmental risks.
    collaborative efforts by many institutions from                                Such debates shape high demands for better weather
    the public, private and academic sectors at                                    and climate information and for services addressing
    national and international levels. As the new                                  the risks and socioeconomic impacts of the weather,
    decade 2021–2030 begins, vigorous NEWP and                                     climate and water hazards. The importance of climate
    high-performance computing (HPC) programmes                                    risk-based decision-making is increasing substantially
    of multidisciplinary research and development                                  with population growth. This is particularly so in major
    (R&D) worldwide are making innovative                                          cities, often on coasts, where more people and assets are
    contributions to this ongoing challenge.                                       exposed and vulnerable to weather, climate, water, ocean
                                                                                   and even space hazards. Essential services (for example,
                                                                                   power, water, transport, telecommunications, the
    Earth-system models are developing in complexity,                              Internet and finance) are also exposed to these hazards.
    incorporating additional processes and needing more                            Meeting the demands for highly localized and accurate
    observations of diverse elements of the environment.                           information with frequent updates, as well as tailored
    Thus, observational and HPC infrastructures are central                        services for informed decision-making over multiple
    to future advancement of NEWP systems. Numerical                               timescales, will require a new level of collaboration
    modelling and prediction were among the main                                   within the weather and climate enterprise2. Working with
    motivations behind the first computer applications 70                          user communities in the co-design of fit-for-purpose
    years ago, and they are still a major use case for HPC                         information and services will also be important.
    today. Likewise, advances in satellite-based observations
    and telecommunications utilized in NEWP are at the                             Traditional risk assessment and management strategies are
    forefront of technological innovations. Computational                          increasingly challenged by systemic risks that connect local
    power and high-quality observations drive improvements                         conditions to broader global systems.These systemic risks
    in weather and climate models such as refined space–                           are unconstrained and include the potential for thresholds
    time resolution, better representation of the physical                         and surprises, along with the need to account for the
    processes and enhanced data-assimilation techniques.                           evolution of weather and climate high-impact events,
    They also help to quantify forecasting and modelling                           variability, and change across time and space. Addressing
    uncertainties, although trade-offs are often required                          such complex risks requires analytical, technical and
    among these. The achievements and improvements are                             deliberative capacity, as well as consideration of equity and
    remarkable; for instance, the mid-latitude 5-day weather                       broader participation to consider implications beyond a
    forecast today is as accurate as the 1-day forecast 40                         single project or decision context.Thus, when considering
    years ago. More accurate and reliable forecasts are                            the future of weather and climate forecasting, the need
    produced by advances in science and technology. These                          for an international multidisciplinary research agenda,

    1 The Earth system encompasses the atmosphere and its chemical composition, the oceans, land/sea ice and other cryosphere components as well
    as the land surface, including surface hydrology and wetlands, lakes and human activities. On short timescales, it includes phenomena that result from
    the interaction between one or more components, such as ocean waves and storm surges. On longer timescales for climate applications, it includes
    terrestrial and ocean ecosystems, encompassing the carbon and nitrogen cycles and slowly varying cryosphere components such as large continental
    ice sheets and permafrost.
    2 The term “weather and climate enterprise” is used to describe the multitude of systems and entities participating in the production and provision
    of meteorological, climatological, hydrological, marine and related environmental information and services. The enterprise includes public-sector
    entities (NMHSs and other governmental agencies), private-sector entities (equipment manufacturers, service-provider companies, private media
    companies, and so forth), academic institutions, and civil society entities (community-based entities, NGOs, national meteorological societies, scientific
    associations, etc.). The weather and climate enterprise has global, regional, national and local dimensions.

3
covering both applications and services, and providing        1.2 Objective and scope of this
for a systematic link between NEWP science and policy/
decision-making, should be recognized.
                                                              White Paper

Over the coming decade, these developments will drive         The main objective of this paper is to provide a basis
many innovations to satisfy diverse socioeconomic             for informed decision-making by weather and climate
needs:                                                        enterprise stakeholders in planning their activities and
                                                              investments in NEWP and operational forecasting during
• Higher-resolution and more localized and relevant           the coming decade. This decade, often referred to as the
  NEWP forecasts, updated frequently (hourly or even          “decade of digital transformation”, will bring profound
  sub-hourly) for cities and other areas of interest. These   impacts on organizations of all types. The weather and
  will be combined with nowcasting tools optimized to         climate enterprise will also undergo significant changes
  provide users with enhanced decision support based          since it is highly driven by data and information technology
  on more timely forecast updates (on a minutes scale)        (IT). The High-level Round Table on the launch of the Open
  before and during high-impact weather.                      Consultative Platform (OCP) Partnership and Innovation for
                                                              the Next Generation of Weather and Climate Intelligence
• Enhanced quality of observational data for analyses         (5–6 June 2019, Geneva) highlighted this expectation, and
  and for assimilation into NEWP systems, as well as          included “Forecasting and … forecasters” among the five
  increased number of Earth-system observations of            themes on key challenges for the next decade (WMO, 2019a).
  all types done in an economic and sustainable way.          This reflects the recognition that the innovation cycle
                                                              (see Figure 1) for weather and climate forecasts includes
• Transition to a full Earth-system numerical prediction      various stakeholders from public, private and academic
  capability with coupled subcomponents, to deliver           sectors. The important drivers of the innovation cycle are
  a wider breadth of information-rich data that are           computational and observational infrastructures (in the
  consistent across the atmosphere, land and ocean,           middle of the figure), and increasing stakeholder and
  including waves, sea ice and hydrological elements.         customer demand (on the circumference of the figure) for
  Aligned with the Earth-system framework and approach,       tailored and seamless weather and climate forecasting
  these NEWP systems will enable prediction of multi-         (localized, timely, precise and accurate). Figure 1 shows
  hazard events in a fully consistent manner, providing       that stakeholders and customers can push clockwise new
  more precise, accurate and reliable information.            initiatives at different positions in the innovation cycle:
                                                              R&D, operation and services.The structure of this paper is
• Seamless weather and climate risk-based services will       aligned along three components of the innovation cycle:
  be further developed, providing insights from minutes       infrastructure, R&D and operation. Stakeholders engaged
  to seasons, to enable improved decision-making              in all three components will have to make strategic choices
  and risk reduction. This will include the integration       in the coming years, and some will struggle to keep up as
  of historical observations and forecasts with a full        technologies continue to combine and advance, and new
  characterization of uncertainty.                            ways of doing business appear quickly.

                                                                                                                                 © iStock

Macedonia

                                                                                                                             4
INFRASTRUCTURE

    Figure 1. The innovation cycle: the public–private engagement challenge

    This paper aims to help decision makers, researchers         Thus, the paper also partly treats elements at the input
    and even users in the rapidly changing landscape of the      side (observational data), as well as at the output side
    weather and climate enterprise, by compiling views,          (generation of products for services) of this chain.
    knowledge and expertise of a group of prominent scientists   Science and research that form the basis for forecasting
    and practitioners from the public, private and academic      and determine its foreseen advances are also discussed.
    sectors. It does not attempt to provide unique solutions     Technology is another key factor in the discussion of
    on the many open questions of the future of weather          the future with many exciting developments in IT and
    and climate forecasting. Instead, it serves to improve       computing that bring enormous opportunities for
    the understanding of ongoing R&D, and to identify            improved quality and efficiency.
    technological trends and sometimes possible impediments
    to progress such as the lack of data sharing. In this way,   The many contributors to this paper were all people
    risks and opportunities for each player can be better        dealing with Earth-system weather and climate numerical
    assessed, and decisions made on future organizational        prediction. However, for the purposes of this paper, they
    plans and investment can be better informed.                 were asked to try to forecast the future of their enterprise.
                                                                 Engaging 27 such contributors may be seen as applying
    The scope of this paper is purposefully restricted to the    the ensemble prediction method, which highlights
    process of NEWP innovation and production of weather         uncertainties and potential different trajectories of
    and climate forecasts, and also to climate insight when      development. Therefore, the individual views and inputs
    there is a close relationship with NEWP and climate          of each contributor are available at the following weblink:
    change science issues. The production value chain in         https://library.wmo.int/doc_num.php?explnum_id=10552.
    the operation (see Figure 1) is increasingly developing      The bibliography at the end of this white paper also
    towards seamless interfaces among its elements.              provides an extensive list of further reading.

5
2. WEATHER AND CLIMATE FORECASTING:
SETTING THE SCENE

2.1 Brief history
Operational weather forecasting and climate predictions       Without going into the details of the pre-NEWP decades
started long before numerical modelling using                 of weather forecast development, it is worth mentioning
computers became possible. There have always been             that the knowledge and methods improved slowly.
attempts to understand weather and climate patterns           However, the number of incorrect forecasts (visible
and eventually foresee their future states, due to the        to the public, due to the popularity of the subject) led
impact on humans and their activities. In the absence         to a prevailing scepticism about the ability of science
of theories and knowledge of the forces driving weather       to deal with the challenge and to make operational
behaviour, such attempts have been part of astrology          forecasting possible with reliable day-to-day outcomes.
or folklore for centuries. There were several important       This may have been the reason for Margules to state,
theoretical advances in the early nineteenth century,         in the early twentieth century, that weather forecasting
including a growing understanding of the nature of            was “immoral and damaging to the character of a
storms. The efforts for organized systematic collection       meteorologist” (Lynch, P., 2006).
of observational data and using these data for predicting
weather events started later in that century. A common        However, developments at the beginning of the twentieth
reference point for the start of “weather forecasting” is     century quickly changed the pessimism of Margules
the work of Admiral FitzRoy during the 1850s and 1860s.       into a much more optimistic scenario for the future of
FitzRoy started issuing storm warnings for sailors in 1860,   weather forecasting. Since the ground-breaking work of
and, one year later, general weather forecasts (the first     Abbe (1901), Bjerknes (1904) and Richardson (1922), the
such forecast appeared in The Times on 1 August 1861).        challenge of NEWP has been related to an initial value
FitzRoy’s work was enabled by the rapidly expanding           conditions problem of mathematical physics (based
use of electrical telegraphs, which allowed collection of     on the non-linear equations governing fluid flow), and
observations from several stations, and some primitive        has been approached using numerical techniques and
situational analysis. It seems he also introduced the use     algorithms.
of the terms “forecast” and “forecasting” in place of
“prognostication”, which had been used previously (BBC        The success of the first numerical prediction by Charney
News, 2015).                                                  et al. (1950) launched a spectacular trend of innovations
                                                              in NEWP over the following seven decades. Routine,
These first attempts at weather forecasting were,             real-time forecasting with NEWP started in the mid-
understandably from today’s perspective, rather               1950s and was introduced in operations in the 1960s.
unsuccessful. Nevertheless, interest in developing            Improved observational coverage, the advent of satellite
knowledge and methods for meteorological analysis             observations, the steady growth of computer power and
and prediction grew rapidly during the last decades           breakthroughs in the theory of Earth-system coupled
of the nineteenth century and the early decades of the        processes all underpinned a successful story of weather
twentieth century. Collecting and exchanging (through         forecasting in the NEWP era.
telegraphs) data across national borders established
one of the early cases of globalized infrastructure and       The high cost of NEWP, including the capital investment
an unprecedented international cooperation between            for computers and their running and maintenance costs,
scientists and practitioners. The “weather knows no           as well as resources needed in R&D, meant that the most
borders” slogan called for a partnership that needed          developed nations had the highest concentration of major
governance – to initiate a global standardization of          developments. Nonetheless, exemplary cooperation and
methods and procedures for research and operations in         knowledge-sharing with scientists from many countries
each individual country.The formal start of such organized    and institutes has nurtured advancement of NEWP.
international cooperation was the first International         European countries undertook a strong collaborative
Meteorological Congress in Vienna in August 1873. This        move with the establishment of the European Centre for
event established a format of collaboration that WMO          Medium-Range Weather Forecasts (ECMWF) in 1975 as
continues today.                                              an intergovernmental organization.

                                                                                                                          6
Progress in NEWP is often illustrated by the improvement       The same study also provided an outlook for Era 5,
    in the horizontal and vertical resolution of operational       encompassing the next 30 years until 2050, which could
    models. There has been an almost 40 times increase in          well be named the era of “next generation of weather
    the horizontal resolution of global models (from about         and climate Earth-system intelligence”.
    400 km in the early 1960s, to less than 10 km in 2020);
    in addition, regional fine-mesh models have reached
    a 1-km resolution. In the vertical direction, from the         2.2 WMO coordination role
    early one- and three-layered quasi-geostrophic models,
    today’s models utilize more than 130 levels, reaching an       It is important to highlight the role of WMO in the
    altitude of about 80 km (pressure of 0.01 hPa).                progress of and insight into weather and climate
                                                                   forecasting. The WMO technical commissions (for
    There are several excellent papers on the history of the       example, the Commission for Atmospheric Sciences,
    highlights of NEWP developments (Pudykiewicz and Brunet,       the Commission for Climatology, the Commission for
    2008; Benjamin et al., 2019; see also Box 2). For example,     Basic Systems, and the Joint Technical Commission
    Benjamin et al. (2019) reviewed the progress in forecasting    for Oceanography and Marine Meteorology) were
    and NEWP applications over the 100-year period from 1919       instrumental in facilitating international collaboration
    to 2019, and divided the period into four ”eras” as follows:   and knowledge-sharing. The World Weather Research
                                                                   Programme and the World Climate Research Programme
    • Era 1 (1919–39: maps only; observations and                  were at the forefront of scientific efforts underpinning
      extrapolation/advection techniques)                          progress in NEWP development and in research-to-
                                                                   operation transition.
    • Era 2 (1939–56: increasing science understanding;
      application especially to aviation; birth of computers)      Establishment of the WWW programme was one of
                                                                   the main WMO contributions. This was initiated on
    • Era 3 (1956–85: advent of NEWP and dawn of                   20 December 1961 with the adoption of Resolution
      remote-sensing)                                              1721 (XVI) by the United Nations General Assembly
                                                                   (United Nations, 1961), which called upon WMO to
    • Era 4 (1985–2018: weather forecasting, and especially        undertake a comprehensive study of measures:
      NEWP, matured and penetrated virtually all areas of
      human activity)

    Box 1. Major milestones in weather and climate forecasting

    • 1861: Met Office weather forecast services using             • 1960 onward: Satellite-based meteorological
      telegraphs established by FitzRoy                              observations and telecommunications at the forefront
                                                                     of technological innovations since the launch of the
    • 1873: Working towards global meteorological                    first weather satellite TIROS-1
      observatories and international data sharing with
      the foundation of the International Meteorological           • 1960s onward: Emergence of general circulation
      Organization in Vienna                                         models for climate research and forecasting

    • 1900–1922: Birth of numerical weather prediction             • 1962: Establishment of the World Weather Watch
      (NWP) with the work of Abbe (1901), Bjerknes (1904)            (WWW) programme with its three main components
      and Richardson (1922)                                          (Global Observing System, Global Telecommunication
                                                                     System and Global Data-Processing System)
    • Early 1920s: Onset of statistical climate prediction and
      global atmospheric teleconnection insights pioneered         • 1963: Lorenz’s seminal work on chaos initiated
      by Walker                                                      atmospheric predictability theory and paved the way
                                                                     to numerical ensemble prediction in the 1980 and 1990s
    • 1950: First computer NWP forecast on ENIAC
      (Electronic Numerical Integrator and Computer) by            • 1969: Launch of the Global Atmospheric Research
      Charney et al. (1950)                                          Program (GARP) led by Charney

7
“(a) To advance the state of atmospheric                composed of three main components: the Global
   science and technology so as to provide greater         Observing System, the Global Telecommunication
   knowledge of basic physical forces affecting            System and the Global Data-Processing and Forecasting
   climate and the possibility of large-scale weather      System (GDPFS), coupled with the Meteorological
   modification;                                           Applications Programme. Thus, the output of the WWW
                                                           system was a global set of observational and forecast
   (b) To develop existing weather forecasting             data that were shared among WMO Member States
   capabilities and to help Member States make             and Territories, and served as input for development
   effective use of such capabilities through regional     of the whole spectrum of user-oriented applications
   meteorological centres”                                 and services.

It is interesting to note the emphasis of “large-scale     Today, GDPFS is an elaborate system of global and
weather modification”, which was hoped would mitigate      regional centres, including nine World Meteorological
the unfavourable weather impacts on human activities.      Centres (WMCs) and 11 Regional Specialized
This hope proved over-optimistic, as became clear in the   Meteorological Centres (RSMCs), with geographical
following decades, and weather modification research       specialization (see Figures 2 and 3). Various centres
and operational activities have not developed much.        are tasked with production of: global deterministic
However, those early intentions for human control on       and ensemble NWP; limited-area deterministic and
weather and climate may be revived to a certain extent     ensemble NWP; nowcasting; various specialized
due to recent geoengineering ideas to mitigate climate     forecasting activities, like tropical cyclone forecasting;
change. However, the gains of geoengineering relative      atmospheric transport and dispersion modelling
to reduced greenhouse gas emissions and against the        (nuclear and non-nuclear); atmospheric sandstorm
hazards it could bring to the environment must be          and duststorm forecasting; numerical ocean wave
balanced rigorously.                                       prediction; aviation forecasting; and so forth. In addition,
                                                           13 centres are designated as Global Producing Centres
Paragraph (b) above of Resolution 1721 is significant      for Long-range Prediction (monthly to seasonal), and
for the scope of this White Paper. In cooperation with     four centres as Global Producing Centres for Annual to
partners, WMO established the WWW programme                Decadal Climate Prediction.

• 1969 onward: Global NWP innovations since the first      • 1997: Ground-breaking numerical prediction advances
  global NWP simulation by Robert                            in the use of multiple sources of Earth-system
                                                             observations with the introduction at ECMWF of four-
• 1975: Federation of global NWP R&D effort in Europe        dimensional data assimilation
  with the foundation of the European Centre for
  Medium-range Weather Forecasts (ECMWF)                   • 2002: Earth Simulator, Japan – a landmark
                                                             supercomputer investment for climate, weather and
• 1979: First GARP Global Experiment, to gather              geophysical research
  the most detailed observations ever of the global
  atmosphere                                               • 2007: A great step forward for weather and climate
                                                             Earth-system forecasting with 3 000 Argo oceanic
• 1980s onward: Development of coupled ocean–                floats in global operation
  atmosphere climate models
                                                           • 2015 onward: Dealing with prediction uncertainty in
• 1992: Operational implementation of ensemble               data assimilation with ensemble–variational data-
  prediction systems at the ECMWF and the National           assimilation techniques
  Centers for Environmental Prediction (NCEP)

                                                                                                                          8
Montreal                                         Tromso       Offenbach
                         Ottawa                                ECMWF                         St Petersburg
 Anchorage
                                                                                             Moscow                           Novosibirsk
                                                              Exeter                         Obninsk                                                  Khabarovsk

       Edmonton                                           Toulouse          Vienna                                                                    Vladivostok

                                        Montreal                             Rome Offenbach
                                                                         Tromso                  Tashkent                                             Tokyio
                                   Washington        Casablanca
    WinnipegAnchorage               Ottawa                      ECMWF Tunis  AthensSt Petersburg
                                                                                              Moscow                         Novosibirsk                              Honolulu
                                                    Barcelona       Exeter                 Cairo
                                                                                              Obninsk                                            Khabarovsk
                              Miami
                  Edmonton                                       Toulouse                     Jeddah
                                                                                          Vienna         Karachi                                 Vladivostok
                                                       Dakar                               Rome                 TashkentNew Delhi                     Beijing
                                                                                                                                                 Tokyio
                                             Washington       Casablanca
               Winnipeg                                                           Tunis   Athens
                                                          Barcelona                          Cairo                                                         Honolulu
                                                                                                                                                     Hong Kong
                                       Miami                     Algier                            Nairobi
                                                                                               Jeddah     Karachi
                                                                                                   Dar es Salaam
                                                               Dakar                                                                              Beijing
              Callao                                                                                                    New Delhi     Darwin
                                                    Brasilia                                                                                                       Nadi
                                                                                                               Vacoas                           Hong Kong
                                                    Niteroi            Algier                        Nairobi
                                                                                                               La Reunion
            Valparaiso                                                                               Dar es Salaam
                          Callao                                                                                                    Darwin
                                               Buenos Aires
                                                         Brasilia
                                                                                          Pretoria                                                          Nadi
                                                                                                               Vacoas
                                                          Niteroi                                                                     Melbourne
                                                                                                               La Reunion
                       Valparaiso                                                                                                                              Wellingtone
                                                     Buenos Aires                           Pretoria
Legend
                                                                                                                                    Melbourne
      World Meteorological Centres (WMCs)* (9)                                                                                                          Wellingtone
                                                                                                                 RSMCs Nuclear Emergency Response** (10)
         Legend
      RSMCs Geographic Specialization (12)                                                                       RSMCs Non-Nuclear Emergency Response** (3)
              World Meteorological
      RSMCs (NRT***) Lead Centre Centres  (WMCs)* (9)of Wave Forecast (1)
                                   for Coordination                                                              RSMCs
                                                                                                                 RSMCsNuclear Emergency
                                                                                                                       Sand and         Response**
                                                                                                                                 Duststorm         (10)(2)
                                                                                                                                            Forecasts
              RSMCs Geographic
      RSMCs (NRT***)           Specialization
                     Lead Centre              (12)
                                 for Coordination  of EPS Verification (1)                                       RSMCs Non-Nuclear Emergency Response** (3)
                                                                                                                 RSMCs Nowcasting (3)
                 RSMCs (NRT***) Lead Centre for Coordination of Wave Forecast (1)                                RSMCs Sand and Duststorm Forecasts (2)
      RSMCs (NRT***) Lead Centre for Coordination of DNV (1)                                                     RSMCs Limited Area Ensemble NWP (2)
                 RSMCs (NRT***) Lead Centre for Coordination of EPS Verification (1)                             RSMCs Nowcasting (3)
      RSMCs Numerical Ocean Wave Prediction (4)                                                                  RSMCs Global Ensemble NWP (7)
                 RSMCs (NRT***) Lead Centre for Coordination of DNV (1)                                          RSMCs Limited Area Ensemble NWP (2)
      RSMCs Tropical Cyclone Forecasting (6)                                                                     RSMCs Limited Area Deterministic NWP (6)
                 RSMCs Numerical Ocean Wave Prediction (4)                                                       RSMCs Global Ensemble NWP (7)
      RSMCs Severe
              RSMCsWeather
                    Tropical Forecasting (5)
                             Cyclone Forecasting (6)                                                             RSMCsLimited
                                                                                                                 RSMCs GlobalArea
                                                                                                                              Deterministic  NWP
                                                                                                                                  Deterministic NWP(8)
                                                                                                                                                    (6)
      RSMCs Severe
              RSMCsWeather Forecasting
                    Severe Weather      (24) (5)
                                   Forecasting                                                                   ICAO designated
                                                                                                                 RSMCs            VolcanicNWP
                                                                                                                       Global Deterministic Ash Advisory
                                                                                                                                                (8)      Centres (9)
                 RSMCs Severe Weather Forecasting (24)                                                           ICAO designated Volcanic Ash Advisory Centres (9)
* World Global Centres are also Global Producing Centres for a) Deterministic Numerical Weather Prediction, b) Ensemble Numerical Weather
Prediction, *and c) Long-Range
              World  Global CentresForecasts.
                                    are also Global Producing Centres for a) Deterministic Numerical Weather Prediction, b) Ensemble Numerical Weather
** RSMC for    nuclear and
            Prediction, andc)non-nuclear   emergency response have Atmospheric Transport and Dispersion Modelling (ATDM) capabilities.
                              Long-Range Forecasts.
*** NRT stands    for Non-Real-Time
            ** RSMC   for nuclear and non-nuclear emergency response have Atmospheric Transport and Dispersion Modelling (ATDM) capabilities.
           *** NRT stands for Non-Real-Time
DESIGNATIONS USED
           DESIGNATIONS USED
The depiction  and use of boundaries, geographic names and related data shown on maps and included in lists, tables, documents, and database
           The depiction and use of boundaries, geographic names and related data shown on maps and included in lists, tables, documents, and database
on this website are not warranted to be error free nor do they necessarily impy official endorsement or acceptance by the WMO.
           on this website are not warranted to be error free nor do they necessarily impy official endorsement or acceptance by the WMO.

         Figure 2. WMO-designated GDPFS centres (nowcasting and weather forecasting, up to 30 days)

         Source: WMO (2019)

9
De Bilt
                                                                                                 Offenbach
                               Montreal
                                                            ECMWF
                                                                                                 Moscow
                                                           Exeter
                                                                                                                                                        Seoul
                                                                                                   Algier
                                                       Toulouse
                                                                    De Bilt
                                                                                          Tunis
                                                                                          Offenbach                                                     Tokyio
                                Montreal           Casablanca
                          Washington                        ECMWF
                                                                                          Moscow
                                                 Barcelona
                                                        Exeter                Tripoli        Cairo
                                                                                                                                             Seoul
                                                                                            Algier
                                                       Toulouse
                                 Bridgetown                                         Tunis
                                                                                                                   Pune                      Tokyio     Beijing
                                                   Casablanca
                            Washington
                                                 Barcelona              Tripoli          Cairo
                                                                                                      Nairobi
                                                                Niamey
         Guayaquil
                                   Bridgetown                                                               Pune                              Beijing
                                                 Brasilia
                                                                                                 Nairobi
                                                 CPTEC        Niamey
              Guayaquil

                                                Brasilia
                                           Buenos Aires                                    Pretoria
                                                 CPTEC                                                                                  Melbourne

                                            Buenos Aires                                Pretoria
Legend
                                                                                                                               Melbourne
     World Meteorological Centres (WMCs)* (9)                                                        RCC - Networks Regional Climate Prediction and Monitoring NODEs (11)
     Legend
     RSMCs (NRT***) Lead Centre for Coordination of ADCP*** (1)                                      RCC Regional Climate Prediction and Monitoring (9)
        World
     RSMCs    Meteorological
           (NRT***)          Centres
                    Lead Centre      (WMCs)*
                                   for       (9)
                                       Coordination of LRFMME**** (2)                            RCC -GPC
                                                                                                      Networks Regional Climate
                                                                                                          for ADCP***     (4) Prediction and Monitoring NODEs (11)
           RSMCs (NRT***) Lead Centre for Coordination of ADCP*** (1)                            RCC Regional Climate Prediction and Monitoring (9)
     RSMCs (NRT***) Lead Centre for Coordination of LRF verification (2)                             GPC for Long-Range Forecasting (13)
           RSMCs (NRT***) Lead Centre for Coordination of LRFMME**** (2)                         GPC for ADCP*** (4)
           RSMCs (NRT***) Lead Centre for Coordination of LRF verification (2)                   GPC for Long-Range Forecasting (13)
* World Global Centres are also Global Producing Centres for a) Deterministic Numerical Weather Prediction, b) Ensemble Numerical Weather
Prediction, and c) Long-Range Forecasts.
** NRT  stands
      * World    for Non-Real-Time.
               Global Centres are also Global Producing Centres for a) Deterministic Numerical Weather Prediction, b) Ensemble Numerical Weather
*** ADCP   stands
      Prediction,   forc)Annual
                  and            to Decadal
                         Long-Range           Climate Prediction
                                     Forecasts.
      ** NRT stands
**** LRFMME           for Non-Real-Time.
                 stands   for Long-Range Forecast Multi-Model Ensemble
     *** ADCP stands for Annual to Decadal Climate Prediction
DESIGNATIONS
      **** LRFMME USED
                     stands for Long-Range Forecast Multi-Model Ensemble
The depiction  and use
      DESIGNATIONS        of boundaries, geographic names and related data shown on maps and included in lists, tables, documents, and database
                       USED
on this website
      The        areand
          depiction   notuse
                           warranted  to begeographic
                             of boundaries, error free names
                                                       nor doand
                                                              they  necessarily
                                                                 related         impy
                                                                         data shown onofficial
                                                                                       maps andendorsement     or acceptance
                                                                                                 included in lists,             by the and
                                                                                                                    tables, documents, WMO.database
     on this website are not warranted to be error free nor do they necessarily impy official endorsement or acceptance by the WMO.

   Figure 3. WMO-designated GDPFS centres (long range and climate forecasting, over 30 days)

   Source: WMO (2019)

                                                                                                                                                                     10
2.3 Baseline 2020

     To provide a vision for developments in weather
     forecasting and climate predictions over the next 10
     years (Vision 2030) and beyond, it is important to set
     up a baseline: the present situation in year 2020. The
     main elements of the ”current state” – baseline 2020 –
     are as follows:

     • High-resolution global deterministic models for the
       medium range operate at horizontal resolutions of
       ~10 km, with 50–140 vertical layers and ~10 prognostic
       variables. These models are usually run for 10–15 days
       with an update cycle of 6 h (four times a day).

     • Ensemble prediction systems for the medium range
       use ~50 ensemble members and the horizontal
       resolution is ~20 km. For an extended range of up to
       45 days, the horizontal resolution is ~35–40 km.

     • As these systems are extended beyond the medium
       range towards the seasonal range, the horizontal
       resolution is usually downgraded to 40–100 km,
       while vertical levels and ensemble size are kept
       constant. Major updates in these systems occur less
       frequently, typically every 5 years or so, with a rate
       of improvement closer to a week of extra lead time
       per decade of development for the Madden–Julian
       oscillation (Kim et al., 2018).

11
3. CHALLENGES AND OPPORTUNITIES
IN THE COMING DECADE

Operational weather forecasting based on                    3.1 Infrastructure for forecasting
numerical prediction systems has continuously
improved over the past few decades. The                     Two main infrastructural elements define the performance
usefulness of NEWP forecasts has been pushed                of NEWP systems: the observational ecosystem that
to lead times beyond 10 days for some high-                 provides the input data and the IT ecosystem including
impact weather phenomena such as mid-latitude               communication, computers and storage, with all internal
snowstorms in North America. However, the                   and external interfaces.
steady progress has been at a slower pace for
some forecasted elements, like quantitative                 The steady improvements in the skill of NEWP are
precipitation, where more efforts are needed.               based, in large part, on the performance of the global
                                                            observing system of systems, which has advanced
                                                            significantly in the past few decades. Recent examples
By 2050, it is envisaged that NEWP will approach the        of such improvements include the development of space-
theoretical limit of mid-latitude predictability of the     based measurements for wind and clouds/precipitation
chaotic atmosphere – a century after the first numerical    using lidar and radar technologies, respectively. Remote-
weather forecasts were produced by Charney and              sensing technologies such as infrared and microwave
his team. Several factors have steered progress,            sounders/imagers in all-sky conditions, combined with
including: advances in NWP underpinned by increasing        advanced ground-based observational networks as the
HPC capacity; improved observational instrumentation        bed-rock, have provided accurate initial conditions that
providing more accurate data with higher temporal and       are a key factor for improved synoptic-scale forecast skill.
spatial resolutions; better representation of complex
physical processes; better model initialization through     In addition to atmospheric measurements, the evolving
the utilization of expanding satellite observations and     capabilities of other Earth-system observations has
more effective data-assimilation methods; and use of        made progression possible towards integrated Earth-
ensembles to represent uncertainty in the initial state     system modelling and forecasting. For example,
and model processes. Furthermore, scientific insight        operational oceanography has increased the availability
across fields ranging from meteorology to computer          of observations necessary to improve ocean state
science has provided a growing suite of tools, catalysing   estimation, including its mesoscale variability. This has
innovations in numerical prediction system design. On       brought rapid improvement in the accuracy of oceanic
the policy side, prevailing free and open data sharing      forecasts. Starting in the 1990s, oceanic measurements,
among countries and institutions has provided access        like Argo floats and Tropical Ocean Global Atmosphere
to observational data for operational and research          arrays, permitted operationalization of forecasts of
purposes, which has facilitated progress. However,          storm surges, waves and sea ice for use by operational
in some areas, policies implying commercial or other        centres. Progress has also been made in land-surface
conditions in accessing important data sets have slowed     hydrology, but much more is needed to advance
the progress.                                               terrestrial hydrology observations and integrate these
                                                            observations into NEWP systems at all timescales.
The increased availability and adoption of forecast-
driven tools for weather- and climate-informed decision-    In contrast to the advances in remote-sensing, there
making, especially by the commercial sector, have           has been alarming evidence that in situ, high-quality
also facilitated major progress. The demand for such        observation systems have decreased in number over
decision-support tools by many industry sectors is          the past 20 years in some regions of the world. Such
growing rapidly when striving to mitigate weather and       negative effects are notable in developing countries
climate impacts on operations and profits. This presents    due to insufficient public funding for operating and
challenges and opportunities for further advancing          maintaining observing networks. The in situ networks
weather and climate forecasting, which is yet to reach      remain foundational for monitoring climate variations
its full potential.                                         and change by serving as reference stations, even
                                                            with the rapid growth of satellite and other remote
                                                            observations. They are also important to climate and
                                                            weather simulations as a reference for the accuracy of

                                                                                                                           12
remote-sensing observations, and for identifying forecast      investing in low-cost technology, often built upon
     errors. Local observations such as weather radars are          research advances, to build short-lifetime missions
     an important part of early warning systems, which              (for example, constellations of nanosatellites). The
     need accurate short-term forecasts of convection and           availability, quality, interest and methods to pay
     other hazards. Various capacity-development projects           for these observations have yet to be evaluated.
     have attempted to fill these observational gaps in the         Public–private arrangements will be needed for
     developing countries, but the success of these efforts         improved coordination of the short- and long-term
     has been undermined by the lack of sustainability and          delivery schedules of these different space-based
     continuity of the operations after the expiration of the       observations and for identifying possible synergies,
     project period.                                                especially where the private sector could fill some
                                                                    observational gaps. Efforts should be made to exploit
     On the IT side, mid-range HPC systems, which nowadays          new satellite observations, and to better utilize the
     are more affordable and accessible, permit effective           data already available. Since many of the advances
     operations and research. This could allow for a wider          in operational prediction are built upon refining and
     range of forecasting centres to operate regional NEWP          improving research breakthroughs, access of the
     systems in partnership with global forecasting providers,      research community to these private sector satellite-
     by enabling demanding computational processes with             based observations is also critical.
     higher space–time resolution in complex settings.
     A significant computational challenge continues to be         • Significant challenges remain in the access to and
     assimilating the ever-increasing volume and variety of          exploitation of data from observing systems owned
     observational data, particularly from satellites.               and operated by various non-State stakeholders. For
                                                                     example, many underutilized in situ weather stations
                                                                     exist, often used for academic purposes, but with
     3.1.1 Observational ecosystem                                   potential to contribute to operational forecasting.
                                                                     Many municipalities, farms, road agencies and other
     Availability of observational data is key to reaching           industries maintain regular observations with their
     the desired model performance, even with the best               own networks of instruments. Such observations
     NEWP model. Thus, discussion about the refinement/              may be of substandard quality compared with those
     development of future NEWP models should go together            operated by National Meteorological and Hydrological
     with that of future observing capabilities. Several factors     Services (NMHSs), but through sharing arrangements
     of the observational ecosystem need to be considered:           and innovative quality control, they could add
                                                                     significantly to the overall observing ecosystem,
     • Overcoming the lack of observational data and data            especially in remote areas, where operation and
       quality issues is critical for continuous improvement.        maintenance of ground stations poses challenges.
       For example, poor instrumentation, particularly in
       developing countries, limits the ground-truthing            • The growing availability of “non-conventional”
       and application of NEWP systems especially at                 observations will offer major new opportunities
       catchment/basin/watershed levels, where most water            for augmenting the classical approaches and filling
       management decisions are usually made.                        existing observational data gaps. There is a plethora
                                                                     of such new data, many available as by-products of
     • Monitoring the Earth’s surface at high temporal               systems or devices not intended for meteorological
       frequency and high spatial resolution will improve            or similar purposes. These include: estimating rainfall
       the description of kilometre and sub-kilometre scales         from attenuation of signals between cell phone
       associated with convective systems, boundary layer            towers, commercial surface sensors purchased and
       processes and new surface types (for example, towns,          deployed by citizens, virtual sensors, “Internet of
       lakes and rivers). Meeting this observational challenge       Things” devices, smartphone sensors and military-
       will be demanding as numerical models move                    grade weather stations. The data provided by these
       towards convective-permitting scales. Boundary layer          new systems or devices offer unprecedented sources
       observations and also observations in data-sparse             of information, but can also present challenges in
       regions would advance forecasting considerably.               terms of observational quality, data access and
                                                                     volumes, and privacy and ethical concerns when data
     • The evolution of satellite programmes for operational         are owned by individuals or commercial companies.
       prediction undertaken by governmental space                   With these concerns addressed appropriately, and
       agencies is stable but takes place over timescales            with proper quality control, such non-conventional
       of decades. The development of satellite remote-              data could deliver observations in sparsely covered
       sensing for the research community has a more rapid           domains like urban areas, tropical land surfaces,
       response. In parallel, the private sector has started         oceans, the upper atmosphere and polar regions.

13
International collection and sharing of such weather        • Projects conducted by leading global weather prediction
  observations is already happening with websites               centres, and the climate projection community (for
  like the Met Office Weather Observation Website.              example, the Coupled Model Intercomparison Project
  However, their systematic use in NEWP should be               (CMIP)), already struggle to afford the sustainable
  cautious since the long-term availability and reliability     supercomputing infrastructures required for hosting
  of such data provision cannot be guaranteed.                  R&D activities and upcoming prediction system
                                                                upgrades, in terms of capital investment and running
• Supplementary information based on indigenous and             operational costs (for example, the cost of electrical
  traditional knowledge and citizen science is yet to be        power). To overcome these challenges, research
  explored as a potential source for improved forecasts         organizations are under increasing pressure to find
  and insights. However, these forms of information             ways to join forces in operating the HPC infrastructure
  remain challenging across several dimensions, such            and gain efficiency through resource and cost sharing.
  as frequency and distribution of collection, mapping
  between epistemological domains and quality control.        • The main technological breakthroughs linked to HPC are
  These challenges can be addressed only through                expected from the combined effects of several sources.
  more systematic and grounded research partnerships.           In the past, an exponential computing power growth
                                                                rate was provided by increasing transistor density while
• Future weather and climate observational data should          maintaining overall power consumption on general-
  be interoperable with socioeconomic, biophysical and          purpose chips. Today, new power-efficient processor
  other data, especially at the local and urban levels,         technologies (for example, graphics processing units,
  to expand knowledge generation and to provide                 tensor processing units, field programmable gate arrays
  informative forecasting results to end users.                 and custom application-specific integrated circuits) are
                                                                increasingly available and necessary to sustain that
• Finally, when planning observational ecosystem                exponential growth.Their use requires code adaptation
  improvements and optimization, it should be kept in           to different ways of mapping operations onto processor
  mind that achievements and improvements in NEWP               memory, parallelization and vectorization. It might be
  systems have permitted the same global forecast               that some of the new processors targeting artificial
  skills to be accomplished utilizing fewer observations,       intelligence (AI) will never be effective at solving
  as demonstrated by reforecast experiments based on            partial differential equations, and it is necessary to seek
  reanalyses. This allows the opportunity to consider           radically new approaches, such as emulation by machine
  optimal and cost-effective design of future operational       learning (ML). The implementation of such adaptation
  observing systems better tailored to the capabilities         will require enough lead time to be effective and serve
  of the forecasting systems. Furthermore, the skill of         the entire community. Furthermore, there is a need to
  NEWP systems often depends more on the ability to             enhance the scope of expertise towards computational
  properly assimilate existing observations, rather than        sciences in all programmes, which offers potential for
  on adding additional observations. Hence, rigorous            attracting new talent and career development.
  forecast sensitivity studies are needed to understand
  the impact of observational data to inform and              • As future architectures will be composed of a wider
  prioritize investments in observational and NEWP              range of different technologies, mathematical methods
  systems at all space–time scales. As an example,              and algorithms need to adapt so computations can
  even with the phenomenal impact of the increase in            be delegated to those parts of the architecture that
  satellite observations for NEWP, in situ observations         deliver optimal performance for each task. Such
  will always be needed to provide a reference, such            specialization is not embodied in present-day codes
  as for surface pressure. However, what the optimal            and not delivered by the available compilers and
  investments in such in situ observations are to satisfy       programming standards. A breakthrough can be
  all user requirements is still an open question.              achieved only by a radical redesign of codes, likely to
                                                                be carried out by the weather and climate community
                                                                in partnership with computer scientists and hardware
3.1.2 High-performance computing ecosystem                      providers. This redesign will ensure the theoretically
                                                                achievable performance gains are scalable from small
The evolution towards running higher-resolution and             to large machines and are transferable to even more
more complex NEWP systems on tight operational                  advanced and novel technologies in the future without
schedules poses significant challenges for HPC and “big         yet another redesign effort.
data” handling. Computing and data must always be
considered together since more sophisticated prediction       • The resulting combination of code adaptivity and
systems create more diverse and more voluminous                 algorithmic flexibility will require a community-wide
output data. Challenges include the following:                  effort; again, there are concerns for computing and

                                                                                                                              14
You can also read