GDAP Current Projects

With a focus on establishing consistency, GDAP oversees a number of assessments of key parameters related to Earth’s energy and water cycles as well as the development of a GEWEX Integrated Product that incorporates several previously supported energy and water flux datasets into a long-term product on a common grid for energy and water cycle closure studies GDAP also sponsors ground-based observing networks that provide high-quality, calibrated, observations for evaluating satellite data sets.


Contact: Dr. Paula Brown

The GEWEX Integrated Product (IP) is the culmination of many GDAP-sponsored data product activities to consolidate the core components of the water and energy cycle into a single consistent dataset on a uniform grid. The IP combines precipitation, clouds, upwelling and downwelling radiative fluxes, turbulent fluxes from GPCP, ISCCP, SRB, LandFlux, and SeaFlux with ancillary surface characteristics, aerosol, and water vapor transports into a single uniform product on a 3 hour, 1 degree equal area grid spanning the 18 year period from 1998 to 2015. While the IP does not ensure consistency in all assumptions across all products, it represents our best effort at synthesizing the diverse products into a coherent set of water and energy parameters.
Available Products: GEWEX Integrated Product



International Satellite Cloud Climatology Project – Next Generation (ISCCP-NG)

GDAP is also coordinating the formation of a new international effort to advance the next-generation International Satellite Cloud Climatology Project (ISCCP). The goal of the ISCCP-NG effort will be to maintain continuity of the ISCCP while developing new global cloud products that exploit the increased spatial and temporal resolution, spectral diversity, and improved calibration afforded by advanced geostationary imagers to support new research and applications.
Through a series of workshops, GDAP is facilitating the gathering of international community input to maximize the benefits of the ISCCP-NG product for meeting user needs.


Guide to Conducting Data Set Quality Assessments
Data Set Quality Assessments: Needs, Benefits, Best Practices and Governance – December 2015

This document addresses the need for systematic assessments of the quality of data sets used in various applications such as climate services and climate science, including their use in the evaluation of climate model performance.

Ongoing Assessments

  • Cloud Assessment Phase II
    Chairs: Claudia Stubenrauch 
(2006 – Present) and 

Stefan Kinne 
(2008 – Present)
    Assessing the reliability of global, long-term cloud data sets.
    For more information see also the Cloud Assessment website.
  • Water Vapor Phase II
    Chairs: Marc Schröder and Lei Shi
    Quantifying the state of the art in water vapor products being constructed for climate applications.
    For more information see also the GEWEX Water Vapor Assessment (GVAP) website.
  • Global Precipitation Products
    Leads: Z. Haddad and R. Roca
    A joint project of the http://www.isac.cnr.it/~ipwg/about.html (CGMS-IPWG) and of GEWEX toward a Broad Scope Assessment of Global Precipitation Products.
    For more information click here.

New Integrated Assessments

  • Earths Energy Imbalance (EEI)
    Leads: Benoit Meyssignac and Tim Boyer
    To address the growing urgency in assessing the fundamental question of where the excess heat in the climate system resulting from increased concentrations of greenhouse gases goes, GDAP has initiated an assessment of the annual mean net energy absorbed by the Earth, referred to as Earth Energy Imbalance (EEI). EEI is a fundamental variable defining the status of global climate change but is very challenging to estimate from observations. A wide range of EEI estimates are available, often with error bars that are difficult to robustly trace to measurement principles. Within the consistency paradigm, GDAP will assess the current available EEI estimates from observations. Since the ocean stores more than 90% of the total planetary heat uptake, the EEI assessment focuses on intercomparing estimates of the time rate of change of ocean heat content (ocean heat uptake). This first EEI assessment will focus on:

    (a) understanding the spread of global and regional ocean heat content and ocean heating rate among products,

    (b) determining systematic errors that depend on assumptions, models, and combined observations, and

    (c) understanding the spread of uncertainties depending on the method and formulae used.”

  • Land Surface
    The GDAP and GLASS panels are initiating a cross-panel land surface energy and water cycle closure assessment that will seek to bridge scales from local/in situ measurements and process models to the large regional domains characterized by satellite products and global models. A community workshop will be held soon to define this activity.