A key factor involved in the exploration of Mars is the possibility that Mars may have harbored life early in its history. As the presence of liquid water is essential for life, NASA is pursuing the identification of aqueous salt minerals on the Martian surface. These minerals include magnesium sulfate of various hydration states, Magnesium Chloride, Calcium Sulfate, Magnesium Perchlorate, Potassium Perchlorate, and Sodium Perchlorate.  Recently, two NASA spacecrafts have returned imagery of mineral salt deposits on the Martian surface and it is hypothesized that these crystalline solids were formed when a salt solution cooled below its so-called eutectic temperature – the point at which everything becomes solidified. These cold salt deposit are known as “cryogenites”. These cryogenites can be crystallographically distinguished from “evaporates”, which are crystals left behind after water has evaporated. It is possible to create laboratory simulations of these aqueous salt deposits that are believed to be in abundance on Mars to compare the morphologies and compositions of the different cryogenites. The temperature and concentration of the solution affect the number of water molecules attached to the resulting crystals and therefore the morphologies of the different crystals. We used multiple cooling methods including walk-in cold rooms, chest freezers, and standard refrigerators to cool our salt solutions below their respective eutectic temperatures. After cooling, some eutectic solids contained ice that needed to be sublimated which further required the use of hydrophilic chemicals such as CaCl2 to pull off the moisture and isolate the salt crystals. Another method we used was to desiccate the solid by freeze drying. After photographing the cryogenite crystals under a microscope, crystal morphologies will be compared with that from the lander imagery. We will examine the lander images in the context of our laboratory images, noting both similarities and differences.

Precipitation varies naturally and with human-caused climate changes, and we are interested in the range of these changes. We use data from the Coupled Model Intercomparison Project Phase 5 (CMIP5) archive, which contains precipitation and energy flux data from 1850 to 2100 from climate model simulations. The comparison of model data from past years with the observed climate record can be used to test the simulations. We use matlab to calculate the mean of precipitation and energy fluxes of each model in CMIP5. The precipitation differences are interpreted with the energy budget. While the precipitation clearly increases in 21st century, there is model-to-model differences over the 20th century. The 20th century differences may be caused by different strengths of aerosol effects related to the second industrial revolution during that period. We will continue data analysis to find the reason for the differences in model predictions over both the 20th and 21st centuries. The differences in the comparision are helpful for validation of the prediction of precipitation in the future and to show the effect of global warming.

Ozone in surface air is toxic to both humans and plants, and has negative implications to human health and crop yields. Surface ozone is enhanced by anthropogenic emissions of nitrogen oxides and hydrocarbons, which are a direct result of fuel combustion and other industrial activities. Yet, the highest concentrations of ozone in California are often observed in the foothills of the Sierra Nevadas, some 50-100 kilometers from the urban plumes of the Sacramento and San Joaquin valleys. How anthropogenic emissions affect ozone in areas strongly influenced by biogenic emissions remains a critical question in our understanding of air quality, with implications for control strategies. To examine these issues we are using data from two multi-year atmospheric chemistry field measurement campaigns: CALNEX SJV and BEARPEX. CALNEX SJV took place in 2010 near Bakersfield, CA, an area heavily influenced by urban and agricultural emissions. The BEARPEX 2007 and 2009 campaigns took place in Blodgett Forest, CA, a rural forested area primarily influenced by biogenic emissions. We are quantifying the extent to which anthropogenic emissions of hydrocarbons affect ozone production in these two regimes by performing a statistical analysis of a unique set of chemical indicators, acyl peroxynitrates, or APN. APN are produced in the atmosphere during the photochemical degredation of hydrocarbons that leads to ozone production. APN carry a fingerprint of an anthropogenic or biogenic hydrocarbon precursor. Through linear combination modeling of ozone using various APN compounds and trend analysis along independent axes such as temperature and day of week, we estimate the relative importance of anthropogenic and biogenic hydrocarbons. Moreover, by comparing data from these two sites, we provide a much broader understanding of such effects in both rural and urban areas.

The effect of evaporative cooling is a common experience that people can relate to. For example Sweat cools us as a result of evaporative cooling. However latent heat is released when liquid water condenses. This transition from gas to liquid brings with it a large amount of energy. This effect is important because it implies that heat is transferred to objects more readily in humid environments. I ran a series of experiments demonstrating this effect. For example, liquid in a soda can will heat almost twice as much in a humid environment as compared to a dry environment at the same temperature.