The Assessment of Stratospheric Aerosol Properties (ASAP) has been carried out by the WCRP project on Stratospheric Process and their Role in Climate (SPARC). The objective of this report is to present a systematic analysis of the state of knowledge of stratospheric aerosols including their precursors. It includes an examination of precursor concentrations and trends, measurements of stratospheric aerosol properties, trends in those properties, and modeling of aerosol formation, transport, and distribution in both background and volcanic conditions.
SAGE-based ASAP Data Products
Below we provide zip files, pdf images, and reader files (IDL) containing gridded and interpolated data sets created as a part of the ASAP effort. In addition to gridded SAGE data fields, ASAP produced a ‘gap-filled’ data set for the period 1979 through 2004 based on the SAGE record. Gaps exist between the June 1991 eruption of Mount Pinatubo and the end of 1993 due to instrument saturation and between November 1981 and October 1984, when global space-based aerosol extinction measurements were not available. To fill the missing values, we have used aerosol backscatter profile measurements from sites at Camaguey (Cuba), Mauna Loa, Hawaii (USA), and Hampton, Virginia (USA) and backscatter sonde measurements from Lauder, New Zealand. This period encompasses the El Chichón eruption and the onset of the Antarctic ozone hole and is, therefore, of particular interest. Beginning in April 1982 and through the beginning of SAGE II observations in 1984, we have used a composite of data consisting of SAM II, the NASA Langley 48-inch lidar system, and lidar data from the NASA Langley Airborne Lidar System. Data from this latter data set has only been partially recovered for the 1982 to 1984 period. If more lidar data from past aircraft missions or a revised Solar Mesospheric Explorer (1981-1986) aerosol product become available, additional work on the El Chichón period would be profitable.
Altitude/Latitude, No interpolation, No filling
Altitude/Latitude, Interpolation, Filled
Potential Temperature/Equivalent Latitude, Interpolation, Filled
Stratospheric Optical Depth (Filled)
Links to Other Data
ASDC (SAGE/POAM/HALOE Data Access)
GES DISC (CLAES Data Access)
OPC (ftp site)