The Pathfinder Atmospheres–Extended AVHRR Climate Dataset

Abstract

ced Very High Resolution Radiometer (AVHRR) Pathfinder Atmospheres?Extended (PATMOS-x) dataset offers over three decades of global observations from the NOAA Polar-orbiting Operational Environmental Satellite (POES) project and the European Organisation for the Exploitation of Meteorological Satellites (EUMETSAT) [Meteorological Operational (MetOp)] satellite series. The AVHRR has flown since 1978 and continues to provide radiometrically consistent observations with a spatial resolution of roughly 4 km and a temporal resolution of an ascending and descending node per satellite per day, achieving global coverage. The AVHRR PATMOS-x data provide calibrated AVHRR observations in addition to properties about tropospheric clouds and aerosols, Earth's surface, Earth's radiation budget, and relevant ancillary data. To provide three decades of data in a convenient format, PATMOS-x generates mapped and sampled results with a spatial resolution of 0.1° on a global latitude?longitude grid. This format avoids spatial or temporal averaging of data, thus maintaining the flexibility to conduct multidimensional analysis. Comparison of this format against the unsampled record demonstrates the ability to reproduce the pixel distribution to a high level of accuracy. AVHRR PATMOS-x is composed of data from 17 different sensors. An examination of cloud amount and total-sky albedo time series demonstrates that intersatellite biases are less than 2%. The comparison of the cloud amount time series to the Interim European Centre for Medium-Range Weather Forecasts (ECMWF) Re-Analysis (ERA-Interim) demonstrates a high degree of correlation, indicating that sensor-to-sensor differences are also not contributing significantly to the observed climate variability in PATMOS-x. AVHRR PATMOS-x data are hosted by the National Climatic Data Center (NCDC) (available at www.ncdc.noaa.gov/cdr/operationalcdrs.html).