Investigating stratospheric changes between 2009 and 2018 with halogenated trace gas data from aircraft, AirCores, and a global model focusing on CFC-11

We present new observations of trace gases in the stratosphere based on a cost-effective sampling technique that can access much higher altitudes than aircraft. The further development of this method now provides detection of species with abundances in the parts per trillion (ppt) range and below. We obtain mixing ratios for six gases (CFC-11, CFC-12, HCFC-22, H-1211, H-1301, and SF6), all of which are important for understanding stratospheric ozone depletion and circulation. After demonstrating the quality of the data through comparisons with ground-based records and aircraft-based observations, we combine them with the latter to demonstrate its potential. We first compare the data with results from a global model driven by three widely used meteorological reanalyses. Secondly, we focus on CFC-11 as recent evidence has indicated renewed atmospheric emissions of that species relevant on a global scale. Because the stratosphere represents the main sink region for CFC-11, potential changes in stratospheric circulation and troposphere–stratosphere exchange fluxes have been identified as the largest source of uncertainty for the accurate quantification of such emissions. Our observations span over a decade (up until 2018) and therefore cover the period of the slowdown of CFC-11 global mixing ratio decreases measured at the Earth's surface. The spatial and temporal coverage of the observations is insufficient for a global quantitative analysis, but we do find some trends that are in contrast with expectations, indicating that the stratosphere may have contributed to the slower concentration decline in recent years. Further investigating the reanalysis-driven model data, we find that the dynamical changes in the stratosphere required to explain the apparent change in tropospheric CFC-11 emissions after 2013 are possible but with a very high uncertainty range. This is partly caused by the high variability of mass flux from the stratosphere to the troposphere, especially at timescales of a few years, and partly by large differences between runs driven by different reanalysis products, none of which agree with our observations well enough for such a quantitative analysis

Washtenaw County Green Infrastructure Development Analysis

A technical report provided to the Washtenaw County Water Resources Office as a final result of the research conducted by the Winter 2021 CLIMATE 592 course.Rain gardens and other types of green infrastructure help reduce surface water runoff from entering nearby water sources. Our goal is to locate areas that would benefit from the installation of green infrastructure, based on the three priority areas of water quality, equity, and wildlife, in the context of a changing climate. In this report, we show our analysis determining ideal locations in Washtenaw County for the development of green infrastructure based on the three priority areas. We incorporate parameters such as land-use tract areas, poverty status data, roadways, precipitation intensity, degraded creeksheds, etc. in order to calculate preference values that will show where to install green infrastructure. Final maps for each of the three priority areas are shown. We also discuss how climate change may affect the locations we have identified in the long term. Green infrastructure has numerous environmental, social, and financial benefits and therefore it may be beneficial for the Washtenaw County Water Resources Office to consider coordinating with SEMCOG and their green infrastructure efforts to increase resilience and avoid maladaptation.http://deepblue.lib.umich.edu/bitstream/2027.42/176118/1/Climate592_FinalReport_2021.pdfDescription of Climate592_FinalReport_2021.pdf : Technical ReportSEL

Investigating stratospheric changes between 2009 and 2018 with halogenated trace gas data from aircraft, AirCores, and a global model focusing on CFC-11

We present new observations of trace gases in the stratosphere based on a cost-effective sampling technique that can access much higher altitudes than aircraft. The further development of this method now provides detection of species with abundances in the parts per trillion (ppt) range and below. We obtain mixing ratios for six gases (CFC-11, CFC-12, HCFC-22, H-1211, H-1301, and SF6), all of which are important for understanding stratospheric ozone depletion and circulation. After demonstrating the quality of the data through comparisons with ground-based records and aircraft-based observations, we combine them with the latter to demonstrate its potential. We first compare the data with results from a global model driven by three widely used meteorological reanalyses. Secondly, we focus on CFC-11 as recent evidence has indicated renewed atmospheric emissions of that species relevant on a global scale. Because the stratosphere represents the main sink region for CFC-11, potential changes in stratospheric circulation and troposphere-stratosphere exchange fluxes have been identified as the largest source of uncertainty for the accurate quantification of such emissions. Our observations span over a decade (up until 2018) and therefore cover the period of the slowdown of CFC-11 global mixing ratio decreases measured at the Earth's surface. The spatial and temporal coverage of the observations is insufficient for a global quantitative analysis, but we do find some trends that are in contrast with expectations, indicating that the stratosphere may have contributed to the slower concentration decline in recent years. Further investigating the reanalysis-driven model data, we find that the dynamical changes in the stratosphere required to explain the apparent change in tropospheric CFC-11 emissions after 2013 are possible but with a very high uncertainty range. This is partly caused by the high variability of mass flux from the stratosphere to the troposphere, especially at timescales of a few years, and partly by large differences between runs driven by different reanalysis products, none of which agree with our observations well enough for such a quantitative analysis

Role of Adiposity-Driven Inflammation in Depressive Morbidity

Depression and metabolic disorders, including overweight and obesity, appear tightly interrelated. The prevalence of these conditions is concurrently growing worldwide, and both depression and overweight/obesity represent substantial risk factors for multiple medical complications. Moreover, there is now multiple evidence for a bidirectional relationship between depression and increased adiposity, with overweight/obesity being associated with an increased prevalence of depression, and in turn, depression augmenting the risk of weight gain and obesity. Although the reasons for this intricate link between depression and increased adiposity remain unclear, converging clinical and preclinical evidence points to a critical role for inflammatory processes and related alterations of brain functions. In support of this notion, increased adiposity leads to a chronic low-grade activation of inflammatory processes, which have been shown elsewhere to have a potent role in the pathophysiology of depression. It is therefore highly possible that adiposity-driven inflammation contributes to the development of depressive disorders and their growing prevalence worldwide. This review will present recent evidence in support of this hypothesis and will discuss the underlying mechanisms and potential therapeutic targets. Altogether, findings presented here should help to better understand the mechanisms linking adiposity to depression and facilitate the identification of new preventive and/or therapeutic strategies.Rôle de l'Inflammation dans la Symptomatologie Neuropsychiatrique chez le Sujet Obès