Linkages of Changes in Ozone to Arctic Climate Change in the Stratosphere and Troposphere

平流层臭氧耗尽是众所周知的现象，这主要是因为南极臭氧层空洞以及对生态系统和人类健康不利影响的担忧。但北极平流层也出现了臭氧消耗，在卫星数据中可以看到臭氧减少了10%到20%，例如，2000年至2005年和1979年至1984年的平均值之间的差异。与南极不同，南极只有一个臭氧空洞，高度从15公里以下延伸到20公里以上，而北极的臭氧消耗有两个明显的峰值，一个在平流层上层35公里到45公里(大约5MB到1MB)，另一个在平流层下层10到15公里(大约200到100MB)。PIS和其他机构的研究提供了令人信服的证据，表明南极臭氧层空洞对平流层和对流层的气候和大气环流产生了重大变化。这些变化包括平流层的冷却和南极洲周围从平流层延伸到地球表面的西风的南移。然而，由于缺乏研究工作，以及卫星对北极上空臭氧估计的差异，尚未确定更为轻微的北极臭氧消耗对气候和环流的类似影响。通过将三个卫星获取的数据集与独立的辐射传输代码和整个大气共同体气候模式(WACCM)相结合，研究北极平流层臭氧损失的影响。WACCM是一个具有良好分辨率的平流层和可选的平流层臭氧化学的大气环流模式。研究的第一阶段是使用辐射传输模型从三个观测数据集中发现的臭氧浓度计算辐射加热率，以确定加热的大小和臭氧浓度差异产生加热差异的程度。这些辐射加热计算之后是WACCM模拟，其中施加了三个数据集的臭氧浓度，使用指定的WACCM化学版本。将使用限于10毫巴以上和10毫巴以下平流层的臭氧变化进行实验，以确定平流层上层的臭氧变化对平流层下层的影响程度，以及上层和下层加热对对流层的影响程度。这些实验的动机是臭氧消耗的双最大结构。最后，WACCM将与交互式气相化学相结合，以便该模型可以在内部模拟臭氧损失，允许臭氧化学受到其产生的温度和环流变化的影响。研究旨在更好地理解北极气候变化和变化的驱动机制，北极气候变化与北极生态系统、冰冻圈和人类活动的社会相关影响具有广泛的联系。此外，北极上空大气环流的变化可能会对北半球中纬度的天气和气候产生重大影响。此外，该项目还为研究生提供支持和培训，从而为在这一领域工作的下一代科学家提供支持。

Stratospheric ozone depletion is a well-known phenomenon, largely because of the Antarctic ozone hole and concerns over adverse effects on ecosystems and human health. But ozone depletion also occurs in the Arctic stratosphere, where reductions of 10% to 20% can be seen in satellite data, for example in differences between the means for years 2000 to 2005 and 1979 to 1984. Unlike the Antarctic, where a single ozone hole extends from altitudes below 15km to above 20km, Arctic ozone depletion has two distinct maxima, one in the upper stratosphere between 35km and 45km (roughly 5mb to 1mb) and one in the lower stratosphere between 10 and 15km (roughly 200 to 100mb). Research by the PIs and others has produced compelling evidence that the Antarctic ozone hole has produced substantial changes in the climate and atmospheric circulation of the stratosphere and troposphere. These changes include stratospheric cooling and a southward shift of the westerly winds around Antarctica that extends from the stratosphere to the Earth's surface. However, analogous climate and circulation impacts of the more subtle Arctic ozone depletion have not been identified, owing partly to lack of research effort and partly to discrepancies in the satellite-derived ozone estimates over the Arctic.Work conducted here addresses the impact of Arctic stratospheric ozone loss by combining three satellite derived datasets with stand-alone radiative transfer codes and the Whole Atmosphere Community Climate Model (WACCM), an atmospheric circulation model with a well-resolved stratosphere and optional stratospheric ozone chemistry. The first stage of the research is to use radiative transfer models to calculate radiative heating rates from the ozone concentrations found in the three observational datasets, in order to determine the magnitude of the heating and the extent to which differences in ozone concentrations yield differences in heating.These radiative heating calculations are followed by WACCM simulations in which the ozone concentrations from the three datasets are be imposed, using the Specified Chemistry version of WACCM. Experiments will be performed using ozone changes restricted to the stratosphere above and below 10mb, to determine the extent to which ozone changes in the upper stratosphere affect the lower stratosphere and the extent to which upper- and lower-level heating affect the troposphere. These experiments are motivated by the dual-maximum structure of the ozone depletion. Finally, WACCM will be integrated with interactive gas-phase chemistry, so that the model can simulate ozone loss internally, allowing the ozone chemistry to be affected by the temperature and circulation changes which it produces.The research seeks to develop a better understanding of the mechanisms driving for climate variability and change in the Arctic, and the Arctic climate change has broad linkages to societally-relevant impacts on ecosystems, the cryosphere, and human activities in the Arctic. Moreover, changes in atmospheric circulation over the Arctic can have substantial consequences for the weather and climate of the middle latitudes of the Northern Hemisphere. In addition, the project provides support and training for a graduate student, thereby providing for the next generation of scientists working in this area.