Role of groundwater in watershed response and land surface feedbacks under climate change

Abstract

[1] We use an integrated, distributed groundwater-surface water-land surface model, ParFlow, to analyze integrated watershed response and groundwater-land surface feedbacks in the Little Washita River watershed, located within the southern Great Plains region of North America, under observed and perturbed climate conditions. Basin-scale hydrologic sensitivity to temperature and precipitation perturbations is shown to be greatest under energy-limited (direct runoff) conditions compared to moisture-limited (base flow) conditions. Feedbacks between groundwater depth and the land surface water and energy balance are shown to significantly influence surface fluxes under moisturelimited conditions, with differences in latent and sensible heat flux between areas of shallow and deep groundwater depth exceeding 75 W/m 2 under strongly energy-limited conditions. The influence of groundwater feedbacks on sensitivity of surface fluxes to changing climate conditions is shown to depend on changes in both moisture and energy availability over the watershed. Results demonstrate that hydrologic sensitivity to climate change depends on feedbacks between groundwater, overland flow, and the land surface water and energy balance. Results suggest not only that local and watershed response to global climate change depends on groundwater feedbacks but that the magnitude and seasonality of these feedbacks is sensitive to changes in climate.

Integrated hydrological modeling of the North China Plain and implications for sustainable water management

“…Large-scale hydrological models have become increasingly popular in assisting water resources management of large aquifer systems (Casper and Vohland, 2008;Goderniaux et al, 2009;Branger et al, 2010). However, great challenges exist in developing and validating such models mainly due to data issues such as unevenly distributed monitoring sites or simply insufficient data (van der Linden and Woo, 2003;Cao et al, 2006;Ferguson and Maxwell, 2010). As a result, the reliability of the model simulations is in question.…”

Spatio-temporal impact of climate change on the groundwater system

“…For example Chen et al (2002), Hsu et al (2006) and SerratCapdevila et al (2007) apply a simple linear function including precipitation and temperature to simulate groundwater recharge, while Woldeamlak et al (2007), Jyrkama and Sykes (2007), van Roosmalen et al (2009), McCallum et al (2010 amongst others apply a more complex approach. Holman (2006), Jyrkama and Sykes (2007), Hendricks Franssen (2009), Ferguson and Maxwell (2010) and Holman et al (2011) advise a physically based approach that accounts for spatial and temporal variation of surface and subsurface properties of the study basin when simulating the impact of climate change on groundwater recharge. A majority of the current studies assessing the impact of climate change on the groundwater system estimate the impact on the annual or seasonal average spatially distributed recharge, e.g.…”

Linking Climate Change and Groundwater

“…The magnitude and seasonality of groundwater feedbacks to surface hydrologic processes is highly sensitive to climate change (Ferguson and Maxwell 2010).…”

“…Groundwater-supported evapotranspiration varied with topography and aquifer-hydraulic conductivity, and small yet important feedbacks exist between groundwater and atmospheric processes on decadal and longer time scales. Moreover, hydrologic sensitivity of a watershed to climate change depends on feedbacks between groundwater, overland flow, and land-surface water and energy balance (Ferguson and Maxwell 2010) as well as the hydrologic regime such as lakes with and without stream outflows (e.g., Hunt et al 2013). …”