@article {174,
	title = {Uncertain monitoring and modeling in a watershed nonpoint pollution program},
	journal = {Land Use Policy},
	volume = {67},
	year = {2017},
	month = {2017/9//},
	pages = {690 - 701},
	abstract = {Performance-based programs governing land use rely on environmental measurement, prediction, and assessment. Yet complex, nonlinear social and environmental change can lead to uncertainties in quantification and forecasting and create challenges for operationalizing programs. This research examines the roles that environmental monitoring and modeling uncertainty play in experimental land and water governance through an analysis of a regulatory water quality program in Wisconsin, USA. The case demonstrates how uncertainties in measurement and prediction of pollution runoff shape program design and participant perceptions. We draw on interviews, a survey, participant observation, and policy document analysis to illustrate how regulators and participants (including municipalities, sewerage treatment plants, farmers and nonprofit organizations) perceive and react to uncertainty. Because current and future water quality data are based largely on model estimates, but regulatory compliance will likely be based on measured in-stream outcomes, participants must evaluate potential risks of involvement. Stakeholders have relied on partnership building and legal modifications such as extended compliance timelines to reduce the risks associated with uncertainty. Experimentation under uncertainty led to sustained stakeholder dialogue, and an iterative process of deciding how monitoring and modeling should be used to track and prove program progress.},
	keywords = {Adaptive governance, Experimental governance, Performance measurement, Regulation, Uncertainty, Water quality, Watershed collaboration},
	isbn = {0264-8377},
	doi = {10.1016/j.landusepol.2017.07.016},
	url = {http://www.sciencedirect.com/science/article/pii/S0264837716312042},
	author = {Wardropper, Chloe B. and Gillon, Sean and Rissman, Adena R.}
}
@article {162,
	title = {Urban heat island-induced increases in evapotranspirative demand},
	journal = {Geophysical Research Letters},
	year = {2017},
	month = {2017},
	abstract = {Although the importance of vegetation in mitigating the urban heat island (UHI) is known, the impacts of UHI-induced changes in micrometeorological conditions on vegetation are not well understood. Here we show that plant water requirements are significantly higher in urban areas compared to rural areas surrounding Madison, WI, driven by increased air temperature with minimal effects of decreased air moisture content. Local increases in impervious cover are strongly associated with increased evapotranspirative demand in a consistent manner across years, with most increases caused by elevated temperatures during the growing season rather than changes in changes in growing season length. Potential evapotranspiration is up to 10\% higher due to the UHI, potentially mitigating changes to the water and energy balances caused by urbanization. Our results indicate that local-scale land cover decisions (increases in impervious cover) can significantly impact evapotranspirative demand, with likely implications for water and carbon cycling in urban ecosystems.},
	keywords = {ecohydrology, plant water use, reference evapotranspiration, urban climatology, urban ecology, urban heat island, Urban systems, Water supply},
	isbn = {1944-8007},
	doi = {10.1002/2016GL072190},
	url = {http://dx.doi.org/10.1002/2016GL072190},
	author = {Zipper, Samuel C. and Schatz, Jason and Kucharik, Christopher J. and Loheide, Steven P.}
}
@article {128,
	title = {Urban heat island effects on growing seasons and heating and cooling degree days in Madison, Wisconsin USA},
	journal = {International Journal of Climatology},
	year = {2016},
	month = {2016},
	abstract = {Urban areas tend to be warmer than their rural surroundings, a phenomenon known as the urban heat island (UHI) effect. UHIs are nearly always described in terms of temperature. However, UHIs can also be described using derived climate indices, including growing season length, growing degree days (GDDs), and heating and cooling degree days, which may have more direct ecological and economic significance than temperature alone. To characterize UHI effects on these basic climate parameters, we used over 3 years of continuously collected temperature data from up to 150 locations in and around Madison, Wisconsin, USA, an urban area of population 402 000 surrounded by lakes and a rural landscape of agriculture, forests, wetlands, and grasslands. Compared to rural areas, Madison{\textquoteright}s UHI extended the freeze-free season by several weeks each year. However, it only shifted the onset of spring and fall (represented by 10-day moving average temperature crossing seasonal thresholds) by 1 day or less in spring and by a few days to a week in fall. The different effects on freeze dates versus running-mean temperatures were primarily because the UHI could affect temperatures during individual freeze events much more than it could influence regional seasonal temperature trends. Urban effects on the meteorological growing season were nearly always greater in fall than in spring. We hypothesize that this is due to seasonal differences in sub-surface temperatures, with urban and rural areas presumably having more uniform sub-surface temperatures in spring after being frozen throughout the winter, contributing to weaker UHI effects in spring than in fall. In terms of degree days, densely built urban areas averaged 14\% (209) more GDDs, 25\% (117) more cooling degree days, and 6\% (284) fewer heating degree days than rural areas, indicating that the UHI could have significant impacts on energy consumption in Madison.},
	keywords = {cooling degree days, energy, freeze dates, growing degree days, growing season, heating degree days, urban climate, urban heat island},
	isbn = {1097-0088},
	url = {http://dx.doi.org/10.1002/joc.4675},
	author = {Schatz, Jason and Kucharik, Christopher J.}
}
@article {137,
	title = {Urban heat island impacts on plant phenology: intra-urban variability and response to land cover},
	journal = {Environmental Research Letters},
	volume = {11},
	year = {2016},
	month = {2016},
	pages = {054023},
	abstract = {Despite documented intra-urban heterogeneity in the urban heat island (UHI) effect, little is knownabout spatial or temporal variability in plant response to the UHI. Using an automated temperaturesensor network in conjunction with Landsat-derived remotely sensed estimates of start/end of thegrowing season, we investigate the impacts of the UHI on plant phenology in the city of Madison WI(USA) for the 2012{\textendash}2014 growing seasons. Median urban growing season length (GSL) estimated fromtemperature sensors is \~{}5 d longer than surrounding rural areas, and UHI impacts on GSL arerelatively consistent from year-to-year. Parks within urban areas experience a subdued expression ofGSL lengthening resulting from interactions between the UHI and a park cool island effect. Acrossall growing seasons, impervious cover in the area surrounding each temperature sensor explains >50\%of observed variability in phenology. Comparisons between long-term estimates of annual meanphenological timing, derived from remote sensing, and temperature-based estimates of individualgrowing seasons show no relationship at the individual sensor level. The magnitude of disagreementbetween temperature-based and remotely sensed phenology is a function of impervious and grass coversurrounding the sensor, suggesting that realized GSL is controlled by both local land cover andmicrometeorological conditions.},
	keywords = {land surface phenology, remote sensing, sensor network, urban climate, urban ecology, urban heat island, vegetation phenology},
	isbn = {1748-9326},
	doi = {10.1088/1748-9326/11/5/054023},
	url = {http://stacks.iop.org/1748-9326/11/i=5/a=054023},
	author = {Samuel C Zipper and Jason Schatz and Aditya Singh and Christopher J Kucharik and Philip A Townsend and Steven P Loheide}
}
@article {103,
	title = {Untangling the effects of shallow groundwater and soil texture as drivers of subfield-scale yield variability},
	journal = {Water Resources Research},
	year = {2015},
	month = {07/2015},
	abstract = {Water table depth (WTD), soil texture, and growing season weather conditions all play critical roles in determining agricultural yield; however, the interactions among these three variables have never been explored in a systematic way. Using a combination of field observations and biophysical modeling, we answer two questions: (1) under what conditions can a shallow water table provide a groundwater yield subsidy and/or penalty to corn production?; and, (2) how do soil texture and growing season weather conditions influence the relationship between WTD and corn yield? Subfield-scale yield patterns during a dry (2012) and wet (2013) growing season are used to identify sensitivity to weather. Areas of the field that are negatively impacted by wet growing seasons have the shallowest observed WTD (< 1 m), while areas with consistently strong yield have intermediate WTD (1-3 m). Parts of the field that perform consistently poorly are characterized by deep WTD (> 3 m) and coarse soil textures. Modeling results find that beneficial impacts of shallow groundwater are more common than negative impacts under the conditions studied, and that the optimum WTD is shallower in coarser soils. While groundwater yield subsidies have a higher frequency and magnitude in coarse-grained soils, the optimum WTD responds to growing season weather at a relatively constant rate across soil types. We conclude that soil texture defines a baseline upon which WTD and weather interact to determine overall yield. Our work has implications for water resource management, climate/land use change impacts on agricultural production, and precision agriculture. This article is protected by copyright. All rights reserved.},
	keywords = {0402 Agricultural systems, 0486 Soils/pedology, 1813 Eco-hydrology, 1829 Groundwater hydrology, agroecosystem modeling, AgroIBIS-VSF, Hydrus-1D, Precision agriculture, soil-plant-atmosphere continuum, water table},
	isbn = {1944-7973},
	doi = {10.1002/2015WR017522},
	url = {http://dx.doi.org/10.1002/2015WR017522},
	author = {Zipper, Samuel C. and Soylu, Mehmet Evren and Booth, Eric G. and Loheide, Steven P.}
}
@article {124,
	title = {Urban climate effects on extreme temperatures in Madison, Wisconsin, USA},
	journal = {Environmental Research Letters},
	volume = {10},
	year = {2015},
	month = {2015},
	pages = {094024},
	abstract = {As climate change increases the frequency and intensity of extreme heat, cities and their urban heatisland (UHI) effects are growing, as are the urban populations encountering them. These mutuallyreinforcing trends present a growing risk for urban populations. However, we have limitedunderstanding of urban climates during extreme temperature episodes, when additional heat from theUHI may be most consequential. We observed a historically hot summer and historically cold winterusing an array of up to 150 temperature and relative humidity sensors in and around Madison,Wisconsin, an urban area of population 402 000 surrounded by lakes and a rural landscape ofagriculture, forests, wetlands, and grasslands. In the summer of 2012 (third hottest since 1869),Madison{\textquoteright}s urban areas experienced up to twice as many hours ⩾32.2 {\textdegree}C (90 {\textdegree}F), mean July T MAX up to1.8 {\textdegree}C higher, and mean July T MIN up to 5.3 {\textdegree}C higher than rural areas. During a record settingheat wave, dense urban areas spent over four consecutive nights above the National Weather Servicenighttime heat stress threshold of 26.7 {\textdegree}C (80 {\textdegree}F), while rural areas fell below 26.7 {\textdegree}C nearlyevery night. In the winter of 2013{\textendash}14 (coldest in 35 years), Madison{\textquoteright}s most densely built urbanareas experienced up to 40\% fewer hours ⩽-17.8 {\textdegree}C (0 {\textdegree}F), mean January T MAX up to 1 {\textdegree}C higher, andmean January T MIN up to 3 {\textdegree}C higher than rural areas. Spatially, the UHI tended to be most intensein areas with higher population densities. Temporally, both daytime and nighttime UHIs tended to beslightly more intense during more-extreme heat days compared to average summer days. These resultshelp us understand the climates for which cities must prepare in a warming, urbanizing world.},
	isbn = {1748-9326},
	doi = {10.1088/1748-9326/10/9/094024},
	url = {http://stacks.iop.org/1748-9326/10/i=9/a=094024},
	author = {Schatz, Jason and Kucharik, Christopher J.}
}
@article {96,
	title = {Using a Simple Apparatus to Measure Direct and Diffuse Photosynthetically Active Radiation at Remote Locations},
	journal = {PLoS ONE},
	volume = {10},
	year = {2015},
	month = {2015/02/10},
	pages = {e0115633 - },
	abstract = {Plant canopy interception of photosynthetically active radiation (PAR) drives carbon dioxide (CO<sub>2</sub>), water and energy cycling in the soil-plant-atmosphere system. Quantifying intercepted PAR requires accurate measurements of total incident PAR above canopies and direct beam and diffuse PAR components. While some regional data sets include these data, e.g. from Atmospheric Radiation Measurement (ARM) Program sites, they are not often applicable to local research sites because of the variable nature (spatial and temporal) of environmental variables that influence incoming PAR. Currently available instrumentation that measures diffuse and direct beam radiation separately can be cost prohibitive and require frequent adjustments. Alternatively, generalized empirical relationships that relate atmospheric variables and radiation components can be used but require assumptions that increase the potential for error. Our goal here was to construct and test a cheaper, highly portable instrument alternative that could be used at remote field sites to measure total, diffuse and direct beam PAR for extended time periods without supervision. The apparatus tested here uses a fabricated, solar powered rotating shadowband and other commercially available parts to collect continuous hourly PAR data. Measurements of total incident PAR had nearly a one-to-one relationship with total incident radiation measurements taken at the same research site by an unobstructed point quantum sensor. Additionally, measurements of diffuse PAR compared favorably with modeled estimates from previously published data, but displayed significant differences that were attributed to the important influence of rapidly changing local environmental conditions. The cost of the system is about 50\% less than comparable commercially available systems that require periodic, but not continual adjustments. Overall, the data produced using this apparatus indicates that this instrumentation has the potential to support ecological research via a relatively inexpensive method to collect continuous measurements of total, direct beam and diffuse PAR in remote locations.},
	doi = {10.1371/journal.pone.0115633},
	author = {Cruse, Michael J. and Kucharik, Christopher J. and Norman, John M.}
}
@article {76,
	title = {Using evapotranspiration to assess drought sensitivity on a subfield scale with HRMET, a high resolution surface energy balance model},
	journal = {Agricultural and Forest Meteorology},
	volume = {197},
	year = {2014},
	month = {2014},
	pages = {91-102},
	abstract = {Abstract Evapotranspiration (ET) rates provide a valuable within-season indicator of plant productivity, as well as data on fluxes of water in a landscape. Applying remote sensing for ET estimation has potential to improve the sustainable management of water resources in agricultural settings. Most current ET models, however, rely on {\textquoteleft}dry{\textquoteright} and {\textquoteleft}wet{\textquoteright} pixels within a given scene to partition turbulent fluxes between latent and sensible heat, thus limiting their ability to map ET throughout the growing season at extremely high (meter scale) spatial resolutions. Here, we develop a field-validated surface energy balance model, High Resolution Mapping of EvapoTranspiration (HRMET), which requires only basic meteorological data, spatial surface temperature and canopy structure data. We use HRMET to estimate ET rates over two commercial cornfields in south-central Wisconsin during the 2012 growing season, which was characterized by severe drought. HRMET results indicate that the magnitude of within-field variability in ET rates was primarily driven by water availability. The application of remotely sensed data to precision agriculture has also been hampered by turnaround time between image acquisition and availability. We introduce relative ET (ETR), which enables comparison of ET rates between image dates by normalizing for variability caused by weather and crop stage. ETR also provides an intuitive, index-like metric for evaluating spatial variability in ET on a subfield scale. ETR maps illuminate persistent patterns in ET across measurement dates that may be driven by soil water availability and topography. ETR is used to develop a novel paired-image technique that can map subfield sensitivity classes to stressors such as drought. Sensitivity class mapping can be used to circumvent issues related to turnaround time to facilitate the incorporation of remotely sensed data into precision agriculture.},
	keywords = {Drought response, Energy balance, Evapotranspiration, Precision agriculture, Spatial heterogeneity, Thermal imagery, Yield monitoring},
	isbn = {0168-1923},
	doi = {10.1016/j.agrformet.2014.06.009},
	url = {http://www.sciencedirect.com/science/article/pii/S0168192314001518},
	author = {Zipper, Samuel C. and Loheide II, Steven P.}
}
