Seite - 174 - in Water, Energy, and Environment - A Primer

temperature and atmospheric greenhouse gas content, the acceleration in sea level rise, the abrupt melting of land ice and ice shelves that had been in place for many thousands of years, and global changes in ocean chemistry. Such changes in these phenomena can only be consistently explained by an unusual rate of greenhouse gas release to the atmosphere.’ Dr J. Marshall Shepherd, President, American Meteorological Society, and Professor of Geography and Director, Atmospheric SciencesProgram,University ofGeorgia • ‘KeyTakeawayPoints: ○ This topic is about impact to people–your constituents, my fellowcitizens,my twokids–not just polar bears. ○Mostof thewarmingof thepast50years isdue tohuman activity,andextensiveevidencesupports thisconclusion. ○Climate change is increasing the probability of extreme events, and in some cases maybe strengthening their intensity or increasing their frequency (i.e., we are loading the dice towards more Sandy or blizzard type storms). ○ There is strong evidence that increases in some types of extremes are linked to human induced climate change, notably extreme heat, coastal flooding, and heavy downpours. For other types of extremes, such as tornadoes, current evidence ismuchmore limited.’ Dr JohnM.Balbus, Senior Advisor for PublicHealth, National Institute of Environmental Health Sciences and Lead Author/ HumanHealth, 2013USNationalClimateAssessment • ‘Rising temperaturewill increasehumanexposure tomold, microbial pathogensand infectiousdiseases.… studies are indicating that the greatest heat-related harm may come not from extreme exposure but rather from the lower but more frequent stress of increasingly hot summerdays.’ Water,Energy, andEnvironment–APrimer174