A Review of Water Quality Responses to Air Temperature and Precipitation Changes 1: Flow, Water Temperature, Saltwater Intrusion

Abstract

Anticipated future increases in air temperature and regionally variable changes in precipitation will have direct and cascading effects on United States (U.S.) water quality. In this paper, and a companion paper by Coffey et al., we review technical literature addressing the responses of different water quality attributes to historical and potential future changes in air temperature and precipitation. The goal is to document how different attributes of water quality are sensitive to these drivers, to characterize future risk to inform management responses, and to identify research needs to fill gaps in our understanding. Here we focus on potential changes in streamflow, water temperature, and salt water intrusion (SWI). Projected changes in the volume and timing of streamflow vary regionally, with general increases in northern and eastern regions of the U.S., and decreases in the southern Plains, interior Southwest, and parts of the Southeast. Water temperatures have increased throughout the U.S. and are expected to continue to increase in the future, with the greatest changes in locations where high summer air temperatures occur together with low streamflow volumes. In coastal areas, especially the mid‐Atlantic and Gulf coasts, SWI to rivers and aquifers could be exacerbated by sea level rise, storm surges, and altered freshwater runoff. Management responses for reducing risks to water quality should consider strategies and practices robust to a range of potential future conditions.

A Review of Water Quality Responses to Air Temperature and Precipitation Changes 2: Nutrients, Algal Blooms, Sediment, Pathogens

“…; USEPA , b; Paul et al. ). Increases in air temperature also alter nutrient biogeochemical cycling, primary productivity, solubility, reaction rates, microorganism survival, evapotranspiration, soil moisture, and other factors related to water quality (e.g., stratification) (Kundzewicz et al.…”

“…A companion paper (Paul et al. ) discusses streamflow, water temperature, and salt water intrusion. We note that water quality changes are complex and affected by multiple, interacting climatic, watershed, and human factors.…”

“…In colder/mountainous areas influenced by snow (e.g., the northern and western U.S.), warmer air temperatures affect the timing and seasonality of snow and snowmelt, including increased winter precipitation in the form of rain as opposed to snow, and snowmelt earlier in the winter and spring. These changes are likely to alter the magnitude and timing of seasonal peak flows, including runoff peaks earlier in the spring, and decrease summer low flows (Birsan et al 2005;Jefferson et al 2008;Ficklin et al 2013;USEPA 2016a, b;Paul et al 2018). Increases in air temperature also alter nutrient biogeochemical cycling, primary productivity, solubility, reaction rates, microorganism survival, evapotranspiration, soil moisture, and other factors related to water quality (e.g., stratification) (Kundzewicz et al 2008;Chang et al 2010;Wear and Greis 2012;Coffey et al 2014;Havens and Paerl 2015;USGCRP 2017).…”

“…In this paper, we focus on potential future responses of nutrients, sediment, pathogens, and cyanobacterial blooms. A companion paper (Paul et al 2018) discusses streamflow, water temperature, and salt water intrusion. We note that water quality changes are complex and affected by multiple, interacting climatic, watershed, and human factors.…”

Featured Collection Introduction: Climate Change Solutions

“…Changes in hydrology alter the sediment and contaminant loading to water bodies and infiltration of chemicals into the subsurface environment. Paul et al () review the literature pertaining to water quality responses to changes in air temperature and precipitation focusing specifically on flow, water temperature, and saltwater intrusion. They conclude climate change effects on water quality will vary in different regional and watershed settings and could present a risk to human health and the environment.…”