Tropical Rainfall Variability on Interannual-to-Interdecadal and Longer Time Scales Derived from the GPCP Monthly Product

Abstract Global and large regional rainfall variations and possible long-term changes are examined using the 27-yr (1979–2005) Global Precipitation Climatology Project (GPCP) monthly dataset. Emphasis is placed on discriminating among variations due to ENSO, volcanic events, and possible long-term climate changes in the Tropics. Although the global linear change of precipitation in the dataset is near zero during the time period, an increase in tropical rainfall is noted in the dataset, with a weaker decrease over Northern Hemisphere middle latitudes. Focusing on the Tropics (25°S–25°N), the dataset indicates an upward linear change (0.06 mm day−1 decade−1) and a downward linear change (−0.01 mm day−1 decade−1) over tropical ocean and land, respectively. This corresponds to an about 5.5% increase (ocean) and 1% decrease (land) during the entire 27-yr time period. The year 2005 has the largest annual tropical total precipitation (land plus ocean) for the GPCP record. The five highest years are (in descendi...

[1]  T. Smith,et al.  Variations in annual global precipitation (1979–2004), based on the Global Precipitation Climatology Project 2.5° analysis , 2006 .

[2]  Kevin E. Trenberth,et al.  Relationships between precipitation and surface temperature , 2005 .

[3]  Mark A. Cane,et al.  Volcanic and Solar Forcing of the Tropical Pacific over the Past 1000 Years , 2005 .

[4]  Nils Wedi,et al.  Comparison of trends and low-frequency variability in CRU, ERA-40, and NCEP//NCAR analyses of surface air temperature , 2004 .

[5]  Xungang Yin,et al.  Comparison of the GPCP and CMAP Merged Gauge-Satellite Monthly Precipitation Products for the Period 1979-2001 , 2004 .

[6]  Tao Zhang,et al.  The Effect of Subtropical Cooling on the Amplitude of ENSO: A Numerical Study , 2004 .

[7]  Ralf Toumi,et al.  Observed Interannual Variability of Tropical Troposphere Relative Humidity , 2004 .

[8]  Arun Kumar,et al.  Differing Trends in the Tropical Surface Temperatures and Precipitation over Land and Oceans , 2004 .

[9]  H. Feidas,et al.  Trend analysis of air temperature time series in Greece and their relationship with circulation using surface and satellite data: 1955–2001 , 2004 .

[10]  H. Su,et al.  The Scatter in Tropical Average Precipitation Anomalies , 2003 .

[11]  J. Neelin,et al.  Tropical drought regions in global warming and El Niño teleconnections , 2003 .

[12]  J. Janowiak,et al.  The Version 2 Global Precipitation Climatology Project (GPCP) Monthly Precipitation Analysis (1979-Present) , 2003 .

[13]  J. Wallace,et al.  The Seasonal Footprinting Mechanism in the Pacific: Implications for ENSO(. , 2003 .

[14]  Michael E. Schlesinger,et al.  Intensity of hydrological cycles in warmer climates , 2003 .

[15]  Robert F. Adler,et al.  Evolution of El Niño‐precipitation relationships from satellites and gauges , 2003 .

[16]  M. Schlesinger,et al.  On the surface and atmospheric temperature changes following the 1991 Pinatubo volcanic eruption: A GCM study , 2002 .

[17]  K. Trenberth,et al.  Evolution of El Niño–Southern Oscillation and global atmospheric surface temperatures , 2002 .

[18]  Alan Robock,et al.  Global cooling after the eruption of Mount Pinatubo: a test of climate feedback by water vapor. , 2002, Science.

[19]  Junye Chen,et al.  Evidence for Strengthening of the Tropical General Circulation in the 1990s , 2002, Science.

[20]  Darren L. Jackson,et al.  Trends in upper‐tropospheric humidity , 2001 .

[21]  T. Wigley.  ENSO, volcanoes and record‐breaking temperatures , 2000 .

[22]  Richard J. Greatbatch,et al.  The North Atlantic Oscillation , 2000 .

[23]  A. Robock.  Volcanic eruptions and climate , 2000 .

[24]  Douglas W. Nychka,et al.  Statistical significance of trends and trend differences in layer-average atmospheric temperature time series , 2000 .

[25]  C. Bretherton,et al.  The Effective Number of Spatial Degrees of Freedom of a Time-Varying Field , 1999 .

[26]  Kevin E. Trenberth,et al.  Progress during TOGA in understanding and modeling global teleconnections associated with tropical sea surface temperatures , 1998 .

[27]  F. Wentz,et al.  Tropical Oceanic Precipitation Changes after the 1991 Pinatubo Eruption , 1998 .

[28]  G. Meehl.  The South Asian Monsoon and the Tropospheric Biennial Oscillation , 1997 .

[29]  J. Wallace,et al.  ENSO-like Interdecadal Variability: 1900–93 , 1997 .

[30]  P. Chu,et al.  Recent Climate Change in the Tropical Western Pacific and Indian Ocean Regions as Detected by Outgoing Longwave Radiation Records , 1997 .

[31]  R. Seager,et al.  Twentieth-Century Sea Surface Temperature Trends , 1997, Science.

[32]  J. Janowiak,et al.  The Global Precipitation Climatology Project (GPCP) combined precipitation dataset , 1997 .

[33]  Michael Ghil,et al.  Quasi-quadrennial and quasi-biennial variability in the equatorial Pacific , 1995 .

[34]  J. Hansen,et al.  Stratospheric aerosol optical depths, 1850–1990 , 1993 .

[35]  Henry L. Gray,et al.  Global warming and the problem of testing for trend in time series data , 1993 .

[36]  R. E. Livezey,et al.  Statistical Field Significance and its Determination by Monte Carlo Techniques , 1983 .

[37]  E. Rasmusson,et al.  Variations in Tropical Sea Surface Temperature and Surface Wind Fields Associated with the Southern Oscillation/El Niño , 1982 .