To further facilitate access and use of the North American Land Data Assimilation System (NLDAS) and Global Land Data Assimilation System (GLDAS) data, two new Giovanni portals, for NLDAS hourly data
and GLDAS 3-hourly data
, have recently been released to the public. Also, the existing Giovanni GLDAS
monthly portal has been updated with GLDAS Version 2 (GLDAS-2) NOAH model data. These new and updated Giovanni portals provide a simple and intuitive way to visualize, analyze, and intercompare NLDAS and GLDAS data without having to download the data.
The Giovanni NLDAS hourly portal
features three NLDAS Version 2 (NLDAS-2) 0.125o
hourly data products (Primary Forcing, Secondary Forcing, and Mosaic Model, for January 1979 - present) and NLDAS Version 1 (NLDAS-1) 0.125o
hourly Forcing data product (August 1996 – December 2007).
The Giovanni GLDAS 3-hourly portal
features the newly released sixty years of 1.0o
3-hourly data (January 1948 – December 2008) from GLDAS-2 NOAH Model Experiment 1 and four GLDAS Version 1 (GLDAS-1) 1.0 o
x 1.0 o
3-hourly data products (January 1979 – present) from the CLM, Mosaic, NOAH, and VIC models.
The Giovanni GLDAS monthly portal
has been updated with the newly released sixty years of 1.0o
monthly data (January 1948 – December 2008) from GLDAS-2 NOAH Model Experiment 1, in addition to the four GLDAS 1.0 o
x 1.0 o
monthly data products (January 1979 – present) from CLM, Mosaic, NOAH, and VIC models.
With these quality-controlled and spatially and temporally consistent, terrestrial hydrological data combined with the simple and convenient Giovanni online visualization and analysis system, NLDAS and GLDAS can play an important role in supporting many different water and energy cycle studies.
Figure 1 is an animated GIF image, generated by the Giovanni NLDAS hourly portal, showing rainfall from Hurricane Irene along the East Coast from Florida to New England hour by hour from August 26-29, with the heaviest rainfall occurring at 13Z August 28, 2011 in New York. “Z” stands for Coordinated Universal Time (UTC), also known as Greenwich Mean Time. The heavy rains during this several -hour-long time period caused significant flooding and damage in many states, particularly the state of Vermont.
Figure 1. Hourly NLDAS data animation of rainfall from Hurricane Irene, August 26-29, 2011.