Submitted to: Journal of Applied Meteorology and Climatology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 12/10/2017
Publication Date: N/A
Interpretive Summary: The effects of long-term warming trends on U.S. agriculture may continue in the coming decades, but it can be difficult to study climate’s impacts on weather-sensitive resources over long periods of time. One way to develop a framework for studying these impacts is to consider the clear effects of temperature on energy consumption. Less natural gas is consumed as conditions warm, while more is consumed under colder conditions. This relationship is clear enough that you can calculate historical natural gas (NG) consumption for each U.S. state based on the state’s historical temperature records. Using monthly temperature records during 1895-2014 and Department of Energy natural gas consumption data during 1990-2013, each state’s monthly NG consumption records during 1895-2014 were estimated. The resulting NG values estimate the effects of 20th century warming trends on each state’s natural gas use, if people were using natural gas under modern (1990-2013) conditions. These 120-year consumption records provide estimates of how sensitive a modern consumer’s NG use would be to historical climate variation, particularly long-term warming trends, that occurred before modern consumption records were available. In addition, they can provide better information about the effects of climate variability on current consumption, and future consumption if long-term temperature trends continue. Long-term warming trends in western and northeastern states may reduce a person’s future consumption, while consumption effects in southeastern states effects reflect a slowly varying temperature cycle with a period of about 60 years. Climate’s effects on a person’s yearly consumption during the 20th century are found to be proportionately small, with reduced consumption due to long-term warming being less than 12%. If those warming trends continue until 2043, they may reduce personal consumption by another 2% on average. But that weak reduction in individual natural gas consumption will have a relatively minor effect on total state consumption, as state population will increase by 25% on average between 2013 and 2043 if current population trends continue.
Technical Abstract: Using state-level monthly heating degree day (HDD) data, per-capita natural gas (NG) consumption records for each state of the continental U.S. were calculated during 1895-2014 using linear regressions. The regressed monthly NG values estimate the effects of 20th and early 21st century climate variation on per-capita natural gas usage, assuming a modern (1990-2013) consumption environment. Using these extended consumption records, the hypothetical effects of climate on past, current, and future NG use are estimated. By controlling for non-climatic consumption effects, these extended reconstructions provide estimates of the sensitivity of NG consumption to historical climate variation, particularly long-term warming trends, occurring before the period of available consumption records. After detrending, the reconstructions are used to form improved estimates of inter-annual NG variation under current climate conditions. Finally, given estimates of each state’s current consumption climatology and long-term trends in per-capita consumption and current population trends, the net effect of warming and increasing population on future consumption is estimated. Significant long-term negative trends in heating-year NG consumption are found in western and northeastern states and Florida, while southeastern consumption effects reflect a multi-decadal temperature cycle. Climate related consumption effects found here are generally consistent with previous studies, with long-term trend effects limited to less than 12%, and multi-decadal regime effects limited to less than 9%. Given the stronger positive effects of increasing population on total state natural gas consumption, reduced per capita use associated with warming trends has a weak moderating effect on estimates of projected total consumption in 2043.