The
CGIAR-CSI GeoPortal provides easy to use
CRU TS 2.1 Global Climate Data for the entire
world. This data has been produced by the
Climatic
Research Unit (CRU) of University of
East Anglia (UEA), and reformatted by International
Water Managment Institute (IWMI) to
provide for easy access and use in geospatial
analysis using common GIS software. Many
thanks to Antonio Trabucco for reformatting
the data, geoprocessing the dataset for
distribution on this site, and providing
the impetus for this effort.
The
CGIAR-CSI
CRU Dataset is provided both in 5 x
5 degrees tiles, and by Continents,
for easy download and use. It is also available
clipped to the Water
for Food Challenge Program (CPWF) Priority
Basin boundaries. These are available as
ArcInfo Grids to facilitate their ease of
use in GIS applications. Data can be searched
and downloaded by tiles from the Search
Page, or by Continents
and Basins,
using a browser, or accessed directly from
the FTP Site. A detailed
explanation of the formatting, methods,
data structure and data dictionary is given
on the CGIAR-CSI
CRU Data Structure Page.
The
CRU TS 2.1 Global Climate Dataset is comprised
of 1224 monthly time-series of climate variables,
for the period 1901-2002, covering the global
land surface, excluding Antarctica, at 0.5
degrees resolution. The nine climate variables
available through this dataset are: daily
mean, minimum and maximum temperature, diurnal
temperature range, precipitation, wet day
frequency, frost day frequency, vapor pressure
and cloud cover. The original CRU TS 2.1
dataset in ascii comma delimited format
is available by ftp. The UEA-CRU
TS 2.1 Data Request Page gives instruction
on how to obtain the CRU original dataset.
CRU
produced the original high-resolution climate
grids (CRU TS 1.0; New et al., 2000) and
an update to 1998 (CRU TS 1.1). Mitchell
et al (2004) revised these grids and extended
them to the year 2000 (CRU TS 2.0). The
CRU 2.1 data-set revises and extends previous
CRU data-sets. The grids have been recalculated
in the version 2.1 for 1901-2002 period,
following a complete revision of the underlying
station databases and using an improved
method. CRU expects to update this dataset
soon, with data up until 2005. CGIAR-CSI
will provide an update when this becomes
available.
It
is strongly recommended that users read
this and associated
articles related to the development
and construction of the CRU dataset. The
issues involved in using CRU TS 2.1 for
time-series analysis are addressed more
explicitly and fully at UEA-CRU
TS 2.0 and Time-Series Analysis: Advice
for Users. The authors of the CRU dataset
recommend that all users who intend to examine
climate change using this data-set should
consider the issues carefully before beginning
their work.
The
creator of this data set (Dr. T. D. Mitchell)
retains full ownership rights over it. The
data set may be freely used for non-commercial
scientific and educational purposes, provided
it is described as CRU TS 2.1 and attributed
to:
