Development of Regional Cloud Climatologies Using a High Spatial Resolution 35-Year AVHRR Cloud and Clear Sky Radiation Property Climate Data Record

A 35-year cloud and clear sky radiation climatology has recently been developed at NASA Langley Research Center and delivered as a Thematic Climate Data Record (TCDR) to the NOAA National Centers for Environmental Information.  This TCDR was generated by the NASA LaRC Satellite ClOud and Radiative Property retrieval System (SatCORPS) using a methodology consistent with MODIS-based cloud analyses within the NASA CERES program.  The TCDR includes parameters such as calibrated shortwave reflectance, cloud detection, phase, temperature, optical depth, and effective particle size, overshooting convective cloud top detection, surface skin temperature, and broadband shortwave albedo and longwave radiative flux.

The products were generated throughout much of the TIROS-N through MetOp-B AVHRR lifetimes at the ~4 km Global Area Coverage (GAC) pixel scale.  A unique aspect of many satellites carrying AVHRR instruments is that their orbits begin to degrade soon after launch.  This means that cloud and clear sky properties have been sampled throughout the diurnal cycle at high spatial resolution when one aggregates AVHRR data across the 35-year time series.  This enables analysis of TCDR time trends and spatial/diurnal cloud distributions at any spatial scale, which is not possible with other sun-synchronous instruments like MODIS that always observe at the same time of day.  

This presentation will show cloud and clear sky temperature trends and distributions across a diversity of regions including the Arctic, the continental U.S., the Amazon rainforest, and over urban areas to highlight what can be learned about mesoscale climate variability from this high spatial resolution AVHRR TCDR dataset.  Diurnal trends in AVHRR TCDR properties will also be compared with a 15-year data record of geostationary imager cloud properties derived within the NASA Clouds and the Earth's Radiant Energy System (CERES) program.