Changes in the Future Statistical Properties of Temperature & Heat Waves in Texas Due to Climate Change

Using both monthly and daily downscaled climate data from the CMIP-5 project, this thesis explored future changes in the statistical properties of temperature and heatwaves. The analysis was conducted for the near-term (2020-2046), mid-century (2047-2073) and end-of-century (2074-2100) across the state of Texas. The results were stratified according to several spatial subsets of Texas including large urban areas and Level 3 ecoregions to identify locally and regionally specific trends. The sensitivity of the findings to various climate scenarios was also evaluated by including two Representative Concentration Pathways (RCPs). Texas as a whole was predicted to increase in average annual temperature by 15.60% for RCP 4.5 and 25.66% for RCP 8.5 from historic 30-year averages (1976-2006) by the end-of-century. Ecoregions in the contiguous northwest of Texas were found to have a greater percent change in temperature than Texas overall or other ecoregions. The largest increase in temperature amongst the urban areas was similarly observed in Dallas. The National Weather Service heat-index method of defining heatwaves identified a limited number of heatwaves since it was applied to broad spatial extents. The magnitude of predicted heatwave events in Houston, the Western Gulf-Coast plains and the Southern Texas plains subsets were found to significantly increase with time. The Dallas urban area was found to have the highest number of future heatwave events, mean event magnitude and average heatwave length. Overall, this research highlights the spatial variability of future heat and heat wave events that will need to be planned for across Texas.