DCV and Hydro-meteorology

Correlation maps between decadal climate variability (DCV) indices and hydro-meteorology variables (precipitation and temperature) on annual and seasonal timescales are here.

We use two gridded precipitation datasets to estimate the associations between DCV phenomena. These datasets are the Global Precipitation Climatology Centre (GPCC) and the Integrated Multi-satellite Retrievals for GPM (IMERG).  GPCC data used are from January 1951 through December 2018 on a global resolution of 1° x 1°. The dataset is updated regularly with a two- to three-month lag.

The IMERG data used are from June 2000 through the current day of the current month on a global resolution of 10km x 10km.  The IMERG data are processed at timescales of every 30 minutes to every monthly.  The monthly version (IMERGM) is calibrated with the GPCC data, therefore also has a two- to three-month lag in availability.  The daily IMERG version (IMERGDL)  is processed after the last observation of the day therefore is available the next day.  The IMERGDL is readily available at the current time, so it will be used in place of the IMERGM in the lagged months for the present conditions. Accordingly, GPCC and IMERGM correlations are used to display past conditions, and both IMERGM and IMERGDL will be used for present conditions.

Temperature data from January 1951 through December 2018 from NCEP/NCAR Reanalysis 1 were used.

You can find here the MRB IMERGM (2000-2017) and GPCC (1961-2010) precipitation, and temperature (1961-2010) climatology.

Annual and seasonal correlations between DCV indices and hydro-meteorological variables can be displayed.

Choose a variable/DCV combination to display:

Major conclusions of these analyses are:
  • Positive and negative phases of DCV phenomena — the PDO, the TAG variability, the WPWP and EIWP variability, and El Niño-La Niña variability — are associated with substantial and significant, annual and seasonal, precipitation and temperature.