Friday 16 July 2010

Space Technology & Global Climate Change


Some of the variables essential for understanding and monitoring the climate system can be efficiently observed from space since this technology enables their systematic, global and homogeneous measurement. With global warming and climate change as major challenges to present and future generations, space technology has become crucial for collecting critical land, ocean and atmospheric data.

Earth Observation from space provides data (satellite data) that are necessary for the scientific foundation of UNFCC and the Kyoto Protocol. Climate Change is a global issue, which must be addressed with global models and global data are needed as input to these models. Earth Observation from space has unique capacity to provide such global data sets in a continuous way. However, Earth Observation from space also provides data on local (National) scales, which can help in the implementation of the convention and protocol, and support the parties in their reporting duties.

The most relevant variables that can be measured from satellite are daily global albedo (fraction of sunlight reflected back from the Earth), vegetation indices, fires and burnt areas, snow cover of both hemispheres, digital elevation maps of the ice sheet surfaces, glaciers evolution and land cover. Some of these variables are required inputs to models designed to better understand the carbon cycle, others give an immediate view of climate change impact.

The large volume of data acquired from satellite observations of sea-surface temperature has given scientists a uniquely detailed view of the changing physical characteristics of the surface of the oceans, sampled at a rate impossible to achieve with only ship-based observations. The data measured independently by several different satellite systems combines into a set of data products that represent the best measure of sea surface temperature, presented in a form that can be assimilated into ocean forecasting models.

Using SAR back-scatter images, the vegetation growth and analysis can be easily achieved with much more efficiency across a broad area. By predicting agriculture outputs well in advance in regions where people still went hungry, space technologies contributes to yet another important development goal - food security.

Thus, satellites provide globally consistent observations and the means to make simultaneous observations of diverse measurements that are essential for climate studies. They supply high-accuracy global observations of the atmosphere, ocean, and land surface that cannot be acquired by any other method. Satellite instruments supply accurate measurements on a near-daily basis for long periods and across broad geographic regions. They can reveal global patterns that ground or air sensors would be unable to detect.

- Rushi GHADAWALA

No comments:

Post a Comment