This dissertation explores the relationship between chironomid communities and the climatic and other environmental variables that are responsible for their distribution over modern, historical, and millennial time scales in the Front Range of the Colorado Rocky Mountains. This study found that surface water temperature, nitrate, boron, and carbon explained the most variance in the modern distibritution of chironomids collected from nine alpine lakes. However, the relationship between surface water temperature (SWT) and nitrate was strongly and negatively correlated suggesting that glacial meltwater is the environmental variable that explains the most control over chironomid communities. Lakes receiving glacial meltwater were 2.62°C colder and contained 66% more nitrate. This is the first evidence that atmospheric deposition of nitrate is affecting benthic invertebrates in the Western United States. This is also the first time that a relationship between boron and chironomid communities has been documented. This finding further substantiates that anthropogenic land-use practices are shaping and influencing remote alpine ecosystems. A high-resolution thermal reconstruction was developed to study the climatic amelioration that occurred at the Pleistocene-Holocene transition. Progressive, three-step warming of SWT was evident for a 3400-year record. Only one period of abrupt climatic amelioration was evident. A dramatic increase of 4.7°C occurred at 11,300 cal yr BP. However, a brief but significant cooling event occurred at 10,570 cal yr BP. These results were found using a chironomid-based SWT inference model (r2boot = 0.38, RMSEP = 2.74°C) that was developed using a lake training set incorporating 153 lakes from California, Utah, and Colorado. No chironomids were present in the sediment corresponding to the Younger Dryas. Reconstructed temperatures ranged from 7.8°C to 13.4°C. Chironomids were used to develop temperature reconstructions for mean July air temperature (MJAT) and SWT for the 20th and 21st centuries and compared to instrumental data for six alpine lakes. Glacial meltwater decoupled the signal between air temperature and water temperature and was evident between the relationships between the predicted MJAT and SWT for lakes receiving meltwater. Within-lake variability may account for discrepancies apparent between the six site locations. Study site selection is crucial for midge-based thermal reconstructions and basins that receive meltwater.