JISAO data
All-India seasonal rainfall anomalies: 1871-1997

September 1998: I calculated my own "All-India" rainfall series using data taken from the World Monthly Surface Station Climatology and the Dai et al. gridded rainfall data set, and obtained a time series with significantly more low-frequency variability than that exhibited by this series. Todd Mitchell
Digital values through 1997 are provided below. The analyses have not yet been updated and only use data through 1995.
Historical record: 1871-1995
Time series image.

Modern record: 1950-95:
Time series image.
 Both figures are for anomalies of June through September seasonal totals. The mean seasonal rainfall for both the historical and modern records is 85 cm, and the series exhibits both year to year and decadal variability. The ordinate units are cm.

This data is provided by B. Parthasarathy of the Indian Institute of Tropical Meteorology, Pune 411 008 India. Please acknowledge Dr. Parthasarathy when using this data.
Seasonal Totals: in tenths mm
The first data value, 849.1 mm, is for 1871.

        +0   +1   +2   +3   +4   +5   +6   +7   +8   +9
 1870      8491 9140 7576 9749 9301 7781 6044 9765 8982
 1880 8206 8617 9033 8497 9333 8480 8748 8998 8120 9311
 1890 9060 7928 9920 9553 9718 8241 8290 8914 8850 6295
 1900 8897 7224 7922 8613 7506 7168 8855 7779 8975 8896
 1910 9354 7368 8064 7848 8985 7810 951110047 6512 8850
 1920 7194 8662 8694 8235 8630 8040 9031 8535 7682 8215
 1930 8049 8776 8038 9762 9138 8439 9087 8424 9086 7899
 1940 8536 7287 9581 8686 9208 9113 9040 9459 8743 9042
 1950 8773 7392 7933 9234 8858 9305 9836 7890 8896 9443
 1960 839910205 8100 8581 9228 7096 7402 8603 7548 8313
 1970 9400 8870 6531 9136 7483 9630 8570 8834 9095 7080
 1980 8829 8524 7356 9559 8369 7600 7432 6974 9617 8669
 1990 9088 7847 7850 8966 9384 8264 8573 8705
Notes on the data:

  • Seasonal-totals provided by Dan Paolino (paolino@cola.iges.org) of the IGES Center for Ocean-Land_Atmosphere Studies (COLA):

         B. Parthasarathy, A.A. Munot, and D.R. Kothwale, 1995:
         'Monthly and seasonal rainfall series for all-India
          homogeneous regions and meteorological subdivisions:
          1871-1994', Contributions from Indian Institute of
          Tropical Meteorology, Pune-411 008, INDIA. 

    All India rainfall is an areal average of 29 subdivisional
 rainfalls.  Subdivisonal rainfalls are from areally averaged
 district rainfalls.  The district rainfall is computed
 from averaging all stations in the district.  Rainfall amounts
 (in millimeters) are totals for June, July, August, and
 September.  
    The data is consistent from 1871 - 1990 in that it is constructed
 from a 306 station network, with no missing data. The number
 and distribution of stations for 1991 - 1994 is unknown.

     Rainfall from Parthasarathy for 1871 - 1994 
     1871 - 1990 from 306 stations, no missing data 
     1991 - 1994 station distribution unknown

     1995 Preliminary rainfall values only. Station distibution
          is unknown.
     1996 from document: IMD New Delhi  Oct 7 1996
          Monsoon 1996 - End-of-the Season Report 
     1997 from document: IMS newsletter (PUNE chapter)
              Oct-Dec 1997 Issue - Vol-II (No. 4)
  • Documentation provided by Todd Mitchell:

    Earlier versions of this time series can be found in:

    Mooley, D. A., and B. Parthasarathy, 1984: Fluctuations in all-India summer monsoon rainfall during 1871-1978. Climatic Change, 6, 287-301.
    Parthasarathy, B., K. Rupa Kumar, and A. A. Munot, 1991: Evidence of secular variations in Indian monsoon rainfall-circulation relationships. J. Climate, 4, 927-938.

    A cursory examination of the seasonal-total values provided in these two publications indicate that they are typically within a few millimeters of those in the table above.
    September 1998
    Todd Mitchell (mitchell@atmos.washington.edu)
    JISAO data