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How ACRE recovers historical weather data

-- By Rob Allan, International ACRE Project Manager, Climate Monitoring and Attribution Group, Met Office Hadley Centre

The International Atmospheric Circulation Reconstructions over the Earth (ACRE) Initiative both undertakes and facilitates the recovery of historical observations of the weather over the terrestrial and marine areas of the Earth’s surface. These observations are vital for underpinning three-dimensional (3D) global weather reconstructions (reanalyses) spanning the last 200-250 years. The great value of such reanalyses is that they can be tailored, shaped, and downscaled for the needs of climate scientists, the diverse climate applications community (for assessments of risks, impacts and extremes), educators, students, and the general public worldwide.

Atmospheric Circulation Reconstructions over the Earth (ACRE) logoACRE is administered by a consortium of seven core partners: the Queensland State Government and the University of Southern Queensland in Australia; the UK Met Office (UKMO) Hadley Centre; the US National Oceanic and Atmospheric Administration (NOAA) Earth System Research Laboratory (ESRL) and the Climate Diagnostics Center (CDC) of the Cooperative Institute for Research in Environmental Sciences (CIRES) at the University of Colorado at Boulder; NOAA’s National Climatic Data Center (NCDC); and the universities of Giessen in Germany and Bern in Switzerland.

The core ACRE partners work with more than 35 projects, institutions, and organisations around the globe in an international context coordinated with the Global Earth Observations System of Systems (GEOSS), the Global Climate Observing System (GCOS), the World Meteorological Organization (WMO), the World Climate Research Programme (WCRP), and the Intergovernmental Ocean Commission (IOC).

The 20th Century Reanalysis Project (20CR)

ACRE's core US partner at ESRL/CDC/CIRES assimilates all of the historical weather observations brought together by the Initiative in order to generate a global reanalyses spanning the last 140 years – the ACRE-facilitated 20th Century Reanalysis Project (20CR). 20CR is the first historical reanalysis of its kind that assimilates only surface variables (synoptic pressure and monthly sea surface temperature and sea-ice) to reconstruct 3D weather variables; it can also be compared with all existing reanalyses. Future reconstructions are planned that will go much further back in time. The historical weather data and the 20CR reanalyses generated from it will be made freely available to all.

ACRE is also working with UK Met Office collaborators applying the PRECIS (Providing REgional Climates for Impacts Studies) model to downscale 20CR output to finer resolution, vastly improving the tailoring and shaping of historical 20CR output for the whole range of user needs internationally.

In addition to its role as an umbrella for efforts to undertake and facilitate international data recovery, imaging and digitization, ACRE has developed, and continues to develop, a range of regional data activities in areas of the globe with currently poor, relatively sparse or difficult to obtain observational coverage.  These foci are:

  • ACRE Chile – initial funding from the European Commission’s 7th Framework Programme (FP7) as part of the ERA-CLIM (European Reanalysis of Global Climate Observations) project
  • ACRE Pacific – led by NIWA (National Institute of Water & Atmospheric Research), New Zealand; initial funding via a French Pacific Fund project
  • ACRE India – linked to a British Library-India initiative
  • ACRE Arctic – being developed by the Atmosphere/Climate Working Group (WG) of the International Arctic Science Committee (IASC)
  • ACRE SE Asia – applying for an Asia Pacific Network (APN) ACRP grant
  • ACRE Africa – a potential event at the upcoming UNFCCC COP-17 conference in Durban, South Africa
  • ACRE China – via a proposal with the Chinese Maritime Customs project at Bristol University, UK

Reaching out

To make 20CR output as user-friendly, tailored, widely-available and interactive as possible, ACRE is embracing the development of technologies in massive-scale data handling and web-based, state-of-the-art, high-resolution visualisations. All of the output from ACRE and its partners (historical surface weather data and the 20CR output) will be showcased on the Met Office-UK Technology Strategy Board-IBM (MO-TSB-IBM) Open Platform that has recently been announced. This Open Platform will provide the vehicle for making the huge amounts of reanalysis output created by 20CR and future longer historical reanalyses easily and freely accessible and available to all users.

A series of recent collaborations between ACRE and partners in the social sciences and humanities has led to broader applications and outreach for reanalysis products; examples include the Shipping Archives and Integrated Logbooks of Ships (SAILS) and Historic Weather projects. Further engagements are developing with the UK National Maritime Museum and have led to ACRE products being used to significantly augment new exhibitions and public displays on various historical themes.  ACRE is also engaging with wider cross-cutting and interdisciplinary initiatives, such as the international student GLOBE Program and its Student Climate Research Campaign (SCRC) for 2011-2013 and the and Data Rescue At Home citizen science projects.

As a result of the above, researchers will be able to evaluate and re-evaluate climatic variability and climate change influences, impacts and modulations on the environment, society, resources and infrastructures. This will be possible on global, regional and also local scales. ACRE-facilitated 20CR activities link closely with the GEO Work Plan and will allow policy makers and scientists alike to address the nature, intensity and frequency of climatic impacts, such as floods, storms and droughts, in ways and over time spans not previously possible.