Observational constraints on climate projections

气候预测的观测限制

• 批准号: 402301-2011
• 负责人: Gillett, Nathan
• 金额: $ 1.52万
• 依托单位: University of Victoria
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2014
• 资助国家: 加拿大
• 起止时间: 2014-01-01 至 2015-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=550865
• 关键词: Observational; constraints; climate; projections

The objective of the proposed research is to use observations of climate change over the past century to improve climate model predictions of future climate change. Climate models are the best available tools for predicting future climate change, providing key information necessary to inform decisions on reducing greenhouse gas emissions, and adaptation to future climate change. However, due to the many complexities of the climate system and uncertainties in its properties, climate model projections of future change in many aspects of the climate differ strongly between models. For example the last United Nations IPCC assessment report concluded that, even given a specific trajectory of 21st century emissions, 21st century global warming could be anywhere from 2.4°C to 6.4°C. While the impacts on society and the environment from a warming of 2.4°C might be manageable, the impacts of a warming of 6.4°C would likely be very severe. Thus it is important to try to reduce these uncertainties, if climate predictions are to be more useful to policymakers and society at large. The proposed research focuses on using observations of past climate change to improve our predictions of future climate change. A large number of climate model simulations are currently being carried out around the world in preparation for the next report of the UN IPCC report. By analysing simulated climate change over both the historical period (1850-2010) and the future, it should be possible to identify robust relationships between simulated past climate change and simulated future climate change. To take a simple example, we might find that models which warm more in the past tend also to warm more in the future. We can then use observations of past climate change, either to rule out some models as being either too sensitive to greenhouse gas increases or not sensitive enough, or we can rescale model projections so that the match to observations is improved. Such research carried out to date has had limited success in constraining future projections. But the availability of new simulations with better models, many finishing in 2010, presents a promising new opportunity to improve our climate projections in this way.

拟议研究的目的是利用过去一个世纪的气候变化观察来改善气候变化。气候模型是预测未来气候变化的最佳工具，提供了为减少温室气体排放和适应未来气候变化的决定所必需的关键信息。但是，由于气候系统的许多复杂性以及其性质中的不确定性，气候模型在气候的许多方面的气候模型预测在模型之间的许多方面都不同。例如，联合国最后一份IPCC评估报告得出的结论是，即使鉴于21世纪排放的特定轨迹，21世纪的全球变暖也可能从2.4°C到6.4°C不多。虽然对社会和环境的影响2.4°C的影响可能是可管理的，但6.4°C的变暖的影响可能非常严重。如果气候预测对政策制定者和整个社会更有用，则重要的是要减少这些不确定性。拟议的研究重点是利用过去气候变化的观察，以改善我们对未来气候变化的预测。目前，全球正在进行大量的气候模型模拟，以准备联合国IPCC报告的下一份报告。通过在历史时期（1850-2010）和未来分析模拟的气候变化，应该可以确定模拟的过去气候变化与模拟未来气候变化之间的牢固关系。举一个简单的例子，我们可能会发现，过去的模型在将来也会更加温暖。然后，我们可以使用对过去气候变化的观察结果，要么排除某些模型对温室气体的敏感或不够敏感，要么我们可以扩展模型项目，从而改善了与观察的匹配。迄今为止，此类研究在限制未来的项目方面取得了有限的成功。但是，具有更好模型的新模拟的可用性，许多在2010年完成的模型，为以这种方式提高了我们的气候预测有希望的新机会。