CLIMATE AND OTHER BIOPHYSICAL ENVIRONMENT PHENOMENA
The effects of human activity on the natural environment coupled with natural changes in the physical climate system make long-term monitoring of the global climate system crucial both to understanding the variability and changes in the Earth system and for providing inputs to model-based prediction schemes. As the human population continues to increase, so too will global demands on agricultural, water, and energy resources. Analyzing regional climate impacts and assessing human vulnerabilities will require high-frequency and spatially dense observations as well as information on the change and rate of change of the global climate system. Regional and national networks must be developed, particularly in regions currently experiencing an increased demand on natural resources. If sufficient observations are not collected, the ramifications will be serious, including less accurate weather forecasts and an inability to monitor natural hazards.
As discussed in Chapter 6, in 1998 the Intergovernmental Panel on Climate Change (IPCC) and the United Nations Framework Convention on Climate Change (UNFCCC) established specific requirements for systematic climate observations and a sustained observing system. Those requirements included supporting research to understand more fully the causes of climate change, to predict future global climate change, and to characterize extreme events important to impact assessments, adaptation, risks, and vulnerability. In 2003 the Second Adequacy Report on the Global Observing System (Global Climate Observing System, 2003) concluded that while improvements had been made in the global observing system, deficiencies remained in the global coverage and quality of ocean, atmosphere, and terrestrial measurements. The report concluded that satellite observations over all domains were essential to the global observing system and that they must continue uninterrupted. Despite such urging, however, U.S. satellite observation capabilities are expected to decline by 25 percent over the next 8 to 10 years, according to a recent National Research Council (NRC) report (National Research Council, 2012) on NASA’s implementation of the Decadal Survey. (See further discussion below.)
The Global Climate Observing System, sponsored by the World Meteorological Organization, the United Nations (UN) Educational, Scientific and Cultural Organization, the UN Environmental Program, and the International Council for Science, is charged with advising the community on global climate observations and overseeing implementation based on UNFCCC standards. In 2010 the organization developed a list of 50 essential climate variables (ECVs) that are possible to implement globally and whose observation could yield significant progress toward meeting the UNFCCC requirements (Global Climate Observing System, 2010). These ECVs are