Open AccessClimatological characteristics of the tropopause parameters derived from GPS/CHAMP and GPS/SAC‐C measurements
Author(s) -
Kishore P.,
Namboothiri S. P.,
Igarashi K.,
Jiang Jonathan H.,
Ao Chi O.,
Romans Larry J.
Publication year - 2006
Publication title -
journal of geophysical research: atmospheres
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.67
H-Index - 298
eISSN - 2156-2202
pISSN - 0148-0227
DOI - 10.1029/2005jd006827
Subject(s) - tropopause , lapse rate , radiosonde , atmospheric sciences , radio occultation , latitude , environmental science , climatology , equator , potential temperature , geology , stratosphere , geodesy , ionosphere , geophysics
We have analyzed the tropopause parameters using the data retrieved from the GPS occultation experiment on board the CHAMP and SAC‐C satellites. In the present study we have considered 3–4 years of data. Tropopause parameters such as temperature, height, pressure, and potential temperature have been separately studied for the tropical and other regions. Comparison of the temperature profiles (obtained near the equator) by the CHAMP and SAC‐C satellites with the radiosonde measurements indicates very good agreement at altitudes below the tropopause. Deviations of 1–2 K are seen above the tropopause level. Analysis of the tropopause parameters separately done for the tropics (20°S–20°N) indicates annual variations. The tropopause temperature and pressure variations are strongly correlated, and they both anticorrelate with the tropopause height. Annual oscillation is evident in the variations of tropopause parameters. The sampled data indicate some interannual variations. We have found that there are some differences between the cold point tropopause (CPT) and lapse rate tropopause (LRT) methods of estimates. The global structure of the tropopause indicates clear differences between the tropics and high‐latitude regions. Seasonal variation is evident in the parameters; however, they are more prominent in the polar regions. The paper confirms that the CHAMP and SAC‐C measurements of the tropopause parameters are complementary as there is very little difference between the two measurements.