An Introduction to Satellite-Based Applications and Research for Understanding Climate Change - Satellite-based Applications on Climate Change - page 2

1.1 Introduction

Climate change is one of most important issues facing the world today. With the Arctic
polar ice extent at near record minimums and new temperature records being set in
many regions of the world, the need to understand how our planet is responding to
environmental change is critical for society. Although some progress was made
toward understanding the changes in weather, the understanding of changes in oceans
and land over time is still in a formative stage. A description of climate observations in
support of the Global Climate Observing System can be found in Thomas R. Karl's
(ed) ( 1996 )book: Long-Term Climate Monitoring by the Global Climate Observing
System. As better quality global observations of the Earth are collected from satellites,
the opportunity to gain insight into the dynamic processes driving our planet and the
long-term trends will improve. Even though there are thousands of surface
observations, rawinsondes, buoys, and other in situ measurements from ships and
aircraft, the observations are limited in global coverage, particularly over the oceans
and the polar caps. Measurements over the sparsely observed oceans and polar caps
are needed to understand how the various regions of our planet are connected. The
land regions where we live are impacted by changes in the oceans and the polar caps.
For example, if the polar caps continue to melt, sea level rise will affect islands and
coastlines - inundating some to such an extent that the inhabitants must live elsewhere.
Changes in temperature will affect precipitation, evaporation, and crop growth,
leading to economic impacts and potential disruptions in global food supply. It is
vital that a fundamental understanding of how our planet works be developed so
accurate predictions of environmental change can be provided. This will allow the
world's decision makers to make tough choices relative to both global and regional
consequences. To garner an improved understanding about how our environment
functions, a comprehensive set of global observations are required. Satellites can
help provide those observations and eliminate the data sparse coverage in many
regions of the world like the oceans, deserts, and polar caps.

1.2 Satellites and Changes over Time

Satellite observations play a crucial role filling the gaps in the data sparse regions
and helping to understand the connections between different regions of the world.
The observations will provide information about how the Earth exchanges energy
between the tropics and the poles and how the heat exchange impacts global
atmospheric circulation patterns as well as the weather and climate trends around
the globe. Satellites are relatively new on the global monitoring scene with only
about 30 years of modern observations. Progress is being made in understanding the
spaceborne observations, how they relate to our collection of in situ observations,
and how they can be used to predict changes in our environment.
In the early years, the first satellites were successful if the imagery had sufficient
contrast and clarity to be used for cloud pattern analysis. One of the first
publications on satellite data applications was the Environmental Science Services