HR: 0830h
AN: A31E-0089    [PDF]
TI: Global Temporal Trends in Surface and Free-Air Equivalent Temperatures at High Elevations
AU: * Pepin, N C
EM: nick.pepin@noaa.gov
AF: NOAA Air Resources Laboratory, NOAA/ARL/R/E/AR 1315 East-West Hwy, Silver Spring, MD 20910 United States
AB: Reconciling differences between temporal trends in surface (land station) and free-air (radiosonde and satellite) temperature data concerns the international scientific community. This paper examines the differences between temporal trends in surface temperature observations at high elevation and interpolated free-air equivalent temperatures from both NCEP/NCAR reanalyses and CARDS (radiosonde data) for recent decades. Preliminary analysis of screen maxima and minima from a range of high elevation SNOTEL (Snow-Telemetry) sites in the western U.S. vs free-air equivalent temperatures interpolated from the NCAR/NCEP reanalysis yielded systematic diurnal and annual signals in the free-air/surface temperature differences. Long-term trends in such differences over the last 20 years are significant at many locations, but vary by magnitude and sign, and are dependent on topography and elevation. Such temporal trends indicate that the Earth's surface may be responding to climate change in a contrasting way to the free atmosphere over this time horizon. Possible mechanisms for such decoupling are discussed.
DE: 0300 ATMOSPHERIC COMPOSITION AND STRUCTURE
DE: 0350 Pressure, density, and temperature
DE: 0399 General or miscellaneous
SC: Atmospheric Sciences [A]
MN: 2003 Fall Meeting