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Recent developments in computational software and public accessibility of gridded climatological data have enabled researchers to study Urban Heat Island (UHI) effects more systematically and at a higher spatial resolution. Previous studies have analyzed UHI and identified significant contributors at the regional level for cities, within the topology of urban canyons, and for different construction materials.
In UHIs, air is heated by the convective energy transfer from land surface materials and anthropogenic activities. Convection is dependent upon the temperature of the surface, temperature of the air, wind speed, and relative humidity. At the same time, air temperature is also influenced by greenhouse gases (GHG) in the atmosphere. Climatologists project a 1-5°C increase in near-surface air temperature over the next several decades, and 1-4°C specifically for Los Angeles and Maricopa during summertime due to GHG effects. With higher ambient air temperatures, we seek to understand how convection will change in cities and to what ends.
In this paper we develop a spatially explicit methodology for quantifying UHI by estimating the daily convection thermal energy transfer from land to air using publicly-available gridded climatological data, and we estimate how much additional energy will be retained due to lack of convective cooling in scenarios of higher ambient air temperature.
Many sites on Mars contain layered sedimentary deposits, sinuous valleys with delta shaped deposits, and other indications of large lakes. The Hypanis deposit is a unique endmember in this set of locations as it appears to be the largest ancient river delta identified on the planet, and it appears to have no topographic boundary, implying deposition into a sea. I have used a variety of high-resolution remote sensing techniques and geologic mapping techniques to present a new model of past water activity in the region.
I gathered new orbital observations and computed thermal inertia, albedo, elevation, and spectral properties of the Hypanis deposit. I measured the strike and dip of deposit layers to interpret the sedimentary history. My results indicate that Hypanis was formed in a large calm lacustrine setting. My geomorphic mapping of the deposit and catchment indicates buried volatile-rich sediments erupted through the Chryse basin fill, and may be geological young or ongoing. Collectively, my results complement previous studies that propose a global paleoshoreline, and support interpretations that Mars had an ocean early in its history. Future missions to the Martian surface should consider Hypanis as a high-value sampling opportunity.