Prioritizing Actions to Adapt America’s Infrastructure for Climate Change—Hydrometeorolgy

The first key message from the US Global Change Research Program (USGCRP) Fourth National Climate Assessment (NCA4) report is that the rate of global climate change substantially outpaces any climatic effects due to natural variability. These changes are manifested in a variety of ways, but the most visible and verifiable indicator is the fact that mean global temperatures have increased substantially during the period of 1901 to 2016, in addition to the fact that there is no credible natural explanation for this increase. The primary cause of global climate change stems from the emissions of greenhouse gases (GHG). The USGCRP found that even if significant reductions in GHGs do occur, global temperatures are projected to continue to increase at an alarming rate beyond the year 2050 compared to preindustrial temperatures. Without such reductions, realized increases in temperature by the year 2100 are projected to be almost three times what they would be if significant reductions are put in place now.

Such extreme upward movements in temperature can affect other meteorological and hydrological design parameters that in turn can have substantial negative impacts on civil engineering infrastructure, resulting in a need to prioritize adaptation activities based partially on the potential impact, frequency, and cost of different future scenarios. A non-comprehensive list of such design parameters include precipitation, stream flow, frequency and intensity of droughts and fires, storm tracks, frequency and intensity of tropical cyclones, sea levels, storm surge, ocean acidity, hail events, ocean wave height and period, intensity and frequency of major wind events, snow pack duration and depth, heatwaves among others. The current status of research related to the projected influence of global warming on many of these factors will be discussed.