 There's a controversy about Earth. It's a controversy about a process that may affect the quality of life in the United States and in every other nation. Scientists don't agree on its impact because its evidence is complex, disturbing and filled with conflicting information. That process is called global warming. National and international initiative is needed to seek new solutions for ozone depletion in global warming and acid rain. Global warming is the phrase used to describe the heating up of the Earth's atmosphere. Why is this an important issue? If the atmosphere heats up by only a few degrees, wind, rain and heat patterns change, damaging vital agricultural areas. The impact? Natural resources would alter. The geopolitical assets of the Earth would shift. A different climate would change the forestry, food and water supply of each nation. Dr. Anthony Del Genio from NASA's Goddard Institute for Space Studies, New York. By the time we get into the middle of the next century, a magnitude of heat wave or drought that we might have only experienced once in the 20th century, we might be experiencing once every 10 years. In order to acquire the information necessary to answer global warming issues, a number of scientific instruments are needed, including an imaging instrument called SAR, Synthetic Aperture Radar. SAR is planned as a part of a mission to planet Earth. NASA's series of Earth-observing satellites. In 1981 and 1984, Dr. Charles Illachi and his colleagues sent an imaging radar into space. They received astonishing data. The radar penetrated the dry sands of the Sahara and discovered ancient riverbeds. This is the most arid region on Earth and it trains once every 40 to 60 years. However, when we look at the radar image which is moving in front of you, you see what seem to be drainage channels and these are the remnant rivers which have dried up because of climatic change. So we know that as recent as the time of the pyramids, that region was not as dry and as arid as it is at the present time. Radar can see through vegetation as well as through clouds. It's as if we could take an x-ray of the inaccessible areas of the Earth. The belts of rainforests around the Earth are critical storehouses of vegetation and thus carbon. Some researchers believe that deforestation is causing significant damage to the Earth's biosphere. However, rainforests are difficult to measure. They are difficult to access and the great bulk of their biomass is hidden by their canopy of tall trees. Dr. Joby Way from NASA's Jet Propulsion Laboratory. Scientists know very well today that atmospheric carbon dioxide is increasing very significantly and we have successfully been able to map the aerial extent of deforestation. But we have never attempted to measure anything about the forest itself, its biomass or its water properties. South will disappear when you get into the equilibrium pressure. The radar, however, can penetrate the entire biomass in the lower understory. You see as you look behind here that there's quite a bit of action going on below this canopy. Radar may be tuned to look at different levels of the biomass, thus electronically penetrating treetops that have veiled the rainforests for so long. At the other extreme of the Earth, the icy oceans of the planet are powerful drivers of global climate. The exchange of heat, gases and energy at the polar regions is immense. Essentially all of the uncertainties in predicting future climate have to do in one way or another with the hydrologic cycle. Anything that involves water and how it changes phase and goes from one form to another is something that we need to know desperately to predict future climate and for which we don't have adequate data sets right now. Sea ice is an important modifier of the Earth's energy. It insulates the warmer ocean below from the freezing winter atmosphere. In cloud-free seasons, it dramatically increases the amount of solar energy reflected back to space. The heat flux through an open area of Arctic Ocean is 100 times more than in an ice-covered area. We know that the polar masses are laced with cracks that expose ocean areas to the air. However, there's a problem at the poles. How do we monitor an area that is obscured with clouds and in darkness for six months of the year? SAR can investigate ice concentration and motion during the long polar night period and through extensive cloud cover. Being able to get that continuous monitoring and the extent of the ice cover and the age of the ice and possibly the thickness of it is a key scientific parameter in that heat exchange between the ocean and the atmosphere. We know with certainty that the burning of fossil fuels is causing significant damage to the Earth's biosphere. The concentration of carbon dioxide in the air has increased by over 10% since 1958 and by nearly 25% since the Industrial Revolution. Heat from the Sun flows past nitrogen and oxygen molecules but is absorbed by CO2. Heat from the Earth is also kept in by CO2, creating an atmospheric blanket. The result? The greenhouse effect. The increased warming of the Earth. However, scientists disagree on whether it will get warmer because global processes are complex. Sunshine, land masses, vegetation, the oceans and the atmosphere are intricately bound in a climatological dance. The Earth is a closed system, a huge global system. NASA's mission to planet Earth, a program to use satellites for the analysis of our own environment, will address questions of potentially great impact to our future. Is global warming occurring? How fast is it occurring? How do man's actions today relate to our past and future climate? EOSAR will explore the dynamics of the Earth as a fragile system in a search for answers to controversial questions.