MERRA Relative Humidity

Retrospective-analyses (or reanalyses) have been a critical tool in studying weather and climate variability for the last 15 years. Reanalyses blend the continuity and breadth of output data of a numerical model with the constraint of vast quantities of observational data. The result is a long-term continuous data record. The Modern Era Retrospective-analysis for Research and Applications was developed to support NASA's Earth science objectives, by applying the state-of-the-art GMAO data assimilation system that includes many modern observing systems (such as EOS) in a climate framework.

The MERRA time period covers the modern era of remotely sensed data, from 1979 through the present, and the special focus of the atmospheric assimilation is the hydrological cycle.

The time period covered by the visualization is the months of May, June, and July of 1988 and 1993, two years with contrasting extreme weather events during the summer: a drought through the midwestern states of the US in 1988, and heavy rains and flooding through the same region in 1993.

This visualization shows the relative humidity dataset produced by MERRA, up to a geopotential height of 20 km. The height coordinate is greatly exaggerated. Both opacity and color are driven by the data value.

This animation was created as part of a presentation for the Nasa Center for Climate Simulation (NCCS) hyperwall display. This is a set of tiled high definition displays consisting of 5 displays across by 3 displays down. The full resolution of all combined displays is 6840 pixels accross by 2304 pixels down. For the full presentation, see the link below.

See the following sources:

• http://gmao.gsfc.nasa.gov/research/merra/
• http://svsdev.gsfc.nasa.gov/vis/a000000/a003700/a003726/