Earth System Evolution

地球系统演化

• 批准号: 9034-2012
• 负责人: Veizer, Jan
• 金额: $ 1.97万
• 依托单位: University of Ottawa
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2012
• 资助国家: 加拿大
• 起止时间: 2012-01-01 至 2013-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=507656
• 关键词: Earth; System; Evolution

Climate Change issues dominate the present day political, social and scientific agenda, with the Intergovernmental Panel for Climate Change (IPCC) predicting an average global temperature rise of 1.5 - 5.5ºC by the end of the century, attributed to greenhouse gases, principally CO2, released into the atmosphere by human activities. Yet, the always present natural greenhouse of about 33ºC is due mainly to water vapour, not CO2. The theoretical idea underpinning all IPCC model "scenarios" is that the addition of energy, attributed to the CO2 greenhouse ("prescribed CO2"), causes more water to evaporate, thus causing a major temperature rise. However, this "positive feedback" may be strongly compensated for by the "negative feedback" of cloud formation, an intractable drawback of the present day climate models. In addition, the water and carbon cycles are coupled, with the former at least as important as the latter for climate considerations. The question now arises, is it the carbon cycle that is the "driver" of the water cycle (as in the IPCC models) or is the carbon cycle mostly "piggybacking" on the water cycle?

气候变化问题主导着当今的政治、社会和科学议程，政府间气候变化专门委员会(IPCC)预测，到本世纪末，全球平均气温将上升1.5-5.5摄氏度，这可归因于人类活动向大气排放的温室气体，主要是二氧化碳。然而，目前一直存在的约33摄氏度的自然温室主要是由于水蒸气，而不是二氧化碳。支持政府间气候变化专门委员会所有模型“情景”的理论思想是，由于二氧化碳温室效应(“规定的二氧化碳”)而增加的能量，会导致更多的水蒸发，从而导致温度的大幅上升。然而，这种“正反馈”可能会被云形成的“负反馈”强烈补偿，这是当今气候模型的一个棘手缺陷。此外，水循环和碳循环是相互关联的，就气候因素而言，水循环至少与碳循环同等重要。现在出现的问题是，碳循环是水循环的“驱动力”(就像在IPCC模型中那样)，还是碳循环主要“搭乘”在水循环上？