GCOS  |   GTOS  |   WMO-CLW  |   HOME     



About GTN-H

Configuration of Network

Network Partners

Global Terrestrial Networks

Hydrological Data Access


GTN-H and


IGWCO 2010 Meeting

2009 Meeting


Selected Global Terrestrial Networks

Global Terrestrial Network of Rivers

The Global Runoff Data Centre’s priority network of about 400 river discharge reference stations along the continental coastline covering around 70% of total continental runoff (GRDC, 2007).

GEMS Water

GEMS Water operates a network of over 3000 stations in more than 100 countries on the state and trends of global inland water quality required as a basis for the sustainable management of the world's freshwater (GEMS/Water, 2007).

International Groundwater Resource Assessment Centre (IGRAC)

The Global Groundwater Monitoring Network (GGMN) aims to improve in-situ monitoring of groundwater resources and to integrate the results of terrestrial observations with those of remote sensing (IGRAC, 2007).

Global Precipitation Climatology Centre (GPCC)

The Global Precipitation Climatology Centre (GPCC) provides raingauge-based monthly precipitation analyses, for monitoring and research of the Earth's climate based on the largest in situ precipitation database in the world. The GPCC comprises data from over 78 000 different stations in more than 180 countries. The map shows the precipitation anomaly for March 2008 in millimeters per month as a departure from the 1961-1990 base period.

International Atomic Energy Agency (IAEA) Global Network of Isotopes in Precipitation (GNIP)

The Global Network of Isotopes in Precipitation (GNIP) programme was initiated in 1958. The main initial objective was the systematic collection of basic data on isotope content of precipitation on a global scale to determine temporal and spatial variations of environmental isotopes in precipitation and, consequently, to provide basic isotope data for the use of environmental isotopes in hydrological investigations within the scope of water resources inventory, planning and development. Although this primary objective remains as an important factor, in recent years, two other objectives have attracted increasing interest: (i) providing input data to verify and further improve atmospheric circulation models, and (ii) the study of climate changes. The database comprises 550 GNIP stations, 389 were judged at present to have sufficient monthly composite d18O, d2H and precipitation amount data to calculate amount-weighted annual and monthly means. The map shows the weighted annual mean for d18O based on the period from 1961 to 1999.