Satellite Remote Sensing Missions for Monitoring Water, Carbon, and Global Climate Change

In recent years, the subjects of water, carbon, and global climate change have attracted worldwide attention by scientists and the media. Climate change, whether associated with humaninduced or natural variations, has and will continue to be important to policy makers and the public. It is clear from reports such as that by the Intergovernmental Panel on Climate Change (IPCC) [1] that Earth observations play a critical role in providing information for assessment and modeling. Improving these observations, better quality and new variables, is a goal of most national and intergovernmental space agencies. Major initiatives are under way that will result in benefits to a broad range of our global society. In the United States, a decadal study [2] was recently completed by the Committee on Earth Science and Applications of the US National Research Council. The committee called for a commitment from the U.S. administration to Earth observations to secure benefits for mankind. The report gives both direction and a large boost to U.S. satellite programs as it recommended NOAA to restore key observational capabilities of satellite missions and also that NASA and NOAA launch 17 new satellite missions in the next 10 years. The study also adds an additional focus to these missions: societal benefits. Other countries have also been expanding their Earth observation programs with numerous advanced concept satellite missions. Of particular relevance to this issue are articles describing the Earth observing programs of the European Space Agency (ESA), the Japanese Aerospace Exploration Agency (JAXA), the China National Space Administration (CNSA), the Canadian Space Agency (CSA), and the National Space Program Office (NSPO) of Taiwan. The ESA has a long history of Earth observation from space that began with meteorological missions and has included a series of increasingly sophisticated radars that have provided valuable data about climate and the changing environment. The ESA’s current and future Earth observing is under its Living Planet Programme and includes the Earth Explorer, meteorological, and Sentinel missions. JAXA has supported a wide range of satellite-based instruments and platforms that have and will provide global Earth observations for water, carbon, and climate. Of particular note for the future is the commitment to the Global Change Observation Mission (GCOM) that will launch a series of two types of satellites (water This Special Issue covers recent and future Earth observing satellites including the purpose of each mission, technology of the measurements, modeling of the physics anddata, image and signal processing.