The US CLIVAR Arctic Change and Possible Influence on Mid-latitude Climate and Weather Working Group was formed in May 2015. The intent of the working group is to further the understanding of the coupling between Arctic variability and mid-latitude climate and weather.
The US CLIVAR Decadal Predictability Working Group was formed to design a framework to distinguish natural decadal variability from anthropogenically forced variability and to quantify their relative magnitude, and develop a framework for understanding decadal variability through metrics to assess and validate decadal climate predictions simulations. They began in 2009 and concluded in 2012.
The US CLIVAR Drought Working Group was formed in 2006 and concluded in 2009.
The US CLIVAR Eastern Tropical Oceans Synthesis (ETOS) Working Group was formed to promote collaboration in the southeast oceanic basins, coordinate a model assessment of surface flux errors for the equatorial Atlantic, identify recent model improvements and common and persistent model errors, and provide recommendations of cases for community simulation and evaluation using eddy-permitting ocean models. They began in 2012 and concluded in 2015.
The US CLIVAR ENSO Diversity Working Group was formed to clarify, coordinate and synthesize research to achieve a better understanding of ENSO diversity, including surface and sub-surface characteristics, tropical-extratropical teleconnections, physical mechanisms predictability, and relationship with climate change. The began in 2012 and concluded in 2015.
The US CLIVAR Extremes Working Group was formed to evaluate whether current climate models produce extremes for the right reasons and whether they can be used for predicting and projecting short-term extremes in temperature and precipitation over North America. They began in 2012 and concluded in 2015.
The US CLIVAR Greenland Ice Sheet-Ocean Interactions Working Group was formed to foster and promote interaction between the diverse oceanographic, glaciological, atmospheric and climate communities, including modelers and field and data scientists within each community, interested in glacier/ocean interactions around Greenland, to advance understanding of the process and ultimately improve its representation in climate models. They began in 2010 and concluded in 2014.
The US CLIVAR High Latitude Surface Flux Working Group was formed with the particular goal of addressing some of the myriad challenges associated with air-sea and air-ice-ocean exchanges in Arctic, Antarctic, and Southern Ocean regions. The working group activities are motivated by several identified deficiencies in estimates of high latitude surface fluxes (e.g., sensible and latent heat, radiative fluxes, stress, and gas fluxes). They began in 2008 and concluded in 2013.
The US CLIVAR Hurricane Working Group was formed to improve understanding of interannual variability and trends in the tropical cyclone activity from the beginning of the 20th century to the present and quantify changes in the characteristics of tropical cyclones under a warming climate. They began in 2011 and concluded in 2014.
The US CLIVAR MJO Working Group was formed in 2006 and concluded in 2010. MJO simulation diagnostics (developed by the working group) are available and hold promise in guiding future model testing and improvement as well as increased sub-seasonal forecast skill. The Working Group has now reformulated as a WCRP/WWRP-THORPEX YOTC Task Force.
The US CLIVAR/OCB Ocean Carbon Uptake Working Group was formed to identify common metrics of physical ocean/climate forcing (primarily wind strength, mixed-layer stratification, and ocean mixing), compare metrics in the various models and in the observations for the North Atlantic and the Tropical Pacific, and coordinate model evaluation of the climatic influence on CO2 uptake at different time scales. They began in 2012 and concluded in 2015.
The US CLIVAR Salinity Working Group was formed to examine the processes and mechanisms that link salinity, the water cycle, ocean circulation, and climate variability; to understand the trends and variability of sea surface salinity and subsurface salinity for different regions; identify the relations between salinity and temperature structure and variability; and determine what observations and monitoring requirements are necessary to ensure adequate salinity data products for future climate studies. They began in 2005 and concluded in 2008.
The US CLIVAR/OCB Southern Ocean Working Group was formed to identify critical observational targets and develop data/model metrics based on the currently available observational data, both physical and tracer, and the assimilative modeling (re)analyses, and evaluate and develop our understanding of the importance of mesoscale eddies in the heat and carbon uptake and of the response of the Southern Ocean to a changing climate, using high-resolution numerical studies and theory. They began in 2012 and concluded in 2015.
The US CLIVAR Western Boundary Current Working Group was charged with identifying shortcomings in the atmosphere, ocean, and coupled models that need to be addressed to accurately model western boundary current atmosphere-ocean interaction. They began in 2007 and concluded in 2010.