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New paper: Modest water policy implementation could offset 30 percent of outdoor demand

July 14, 2020

A new paper in Sustainability Science finds that the use of alternative water supplies, such as rainwater harvesting and greywater use, could offset up to 30 percent of total outdoor water demand for the Phoenix Metropolitan Area under modest implantation of these policies.

The paper, Simulating alternative sustainable water futures, is the work of sustainability scientists David Sampson and Nancy Grimm, sustainability fellow David Iwaniac, UREX affiliate Elizabeth Cook and CAP LTER affiliate Melissa Davidson. The authors adapted ASU’s WaterSim tool to explore differences in water demand and supply, as influenced by runoff, rainfall, changes in land use and land cover, population growth and improvements in water use efficiency.

The abstract follows.

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In an interdisciplinary effort, ASU researchers develop a framework to help decide sustainable futures

Science Direct | February 1, 2020

Image of wind turbinesAs we continue to witness the devastating impacts of climate change, there is a consensus that we as a human population need to transition to a more sustainable way of living. But with so many ideas and proposals, how do we decide which pathways are best? Experts from Arizona State University have created a tool to help: The Sustainable Future Scenarios (SFS).

According to a new paper published in the journal of Landscape and Urban Planning, "The co-production of sustainable future scenarios," the SFS “offers guidance to co-produce visions and transition pathways of positive futures that develop and integrate interventions for sustainability transformations of social-ecological-technological systems.”

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CAP LTER Seeking Postdoctoral Fellow

July 23, 2019

Tempe Town Lake at nightExplore opportunities for building positive futures by becoming a CAP LTER postdoctoral fellow. The fellow works with the Scenarios and Futures research team, focusing on scenario co-development and spatially-explicit scenario modeling of urban change under possible alternate future scenarios. He or she plays a key role in the scenario-development process, modeling, analysis and visualization.

The fellow’s postdoctoral research includes understanding trade-offs associated with possible interventions for social, ecological and technical domains of urban systems, as well as assessing how urban change will affect the future ability of ecosystems to provide services for sustainability, resilience and equity. Find additional details and apply here.

ASU experts creating solutions and mitigation strategies for extreme heat dangers

View Source | May 24, 2019

Downtown Phoenix skyline with yellow skyIn recognition of Arizona Heat Awareness Week May 27 through May 31, ASU Now is highlighting a slew of projects and initiatives that are expanding our understanding and capabilities as they concern the inescapable environmental reality of scorching temperatures.

The article, "Summer in the City," highlights the work of several senior sustainability scientists and fellows: Mikhail Chester, Ariane Middel, David Hondula, Nancy Selover, Sharon Harlan and Matei Georgescu.

All of these faculty are affiliated with the Central Arizona–Phoenix Long-Term Ecological Research program, a unit of the Julie Ann Wrigley Global Institute of Sustainability.

Grimm, Elser elected to National Academy of Sciences

View Source | May 3, 2019

Old Main buildingBeing elected to the National Academy of Sciences is one of the highest honors for a scientist, and it also means that members are qualified to inform the president and Congress about issues related to their expertise. Two Arizona State University sustainability scientists, Nancy Grimm and James Elser, can now add that accolade to their already celebrated resumes.

The National Academy of Sciences (NAS) is an honorific society of distinguished scholars engaged in scientific and engineering research dedicated to the advancement of science and technology and to their use for the general welfare of society. The academy announced Tuesday the election of 100 new members and 25 foreign associates in recognition of their distinguished and continuing achievements in original research.

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Sustainability scientist serves on new environmental economics advisory committee

April 22, 2019

Keryy SmithASU faculty helps establish research organization to strengthen the Environmental Protection Agency's ability to assess social benefits and costs of environmental policies

Policies on air pollution, climate change and water have far-reaching effects on millions of Americans and businesses. Is the Environmental Protection Agency ─ the federal agency whose mission is to protect public health and the environment ─ using the best available economic science when designing and proposing such policy? The newly created External Environmental Economics Advisory Committee (E-EEAC) will convene nationally recognized environmental economists to ensure that it does.

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Streamlining the study of nature in cities

View Source | April 22, 2019

Nancy GrimmNancy Grimm, an Arizona State University professor in the the School of Life Sciences and a senior sustainability scientist, won an award for being part of a team that created an international consensus on how to approach urban ecology.

Along with nine co-authors, Grimm won the 2019 Sustainability Science Award from the Ecological Society of America. Grimm and her colleagues provided “an international perspective on how ecological research focused on urban areas can improve sustainability,” according to the society’s citation. “Urban areas are expected to be highly at risk from global environmental changes and this article highlights the need for a conceptual synthesis that allows urban residents to make better decisions concerning their environment and the social relations within it.”

Sustainability scientist Nancy Grimm wins fellowship

March 8, 2019

Nancy Grimm working in the fieldSenior Sustainability Scientist Nancy Grimm, the Virginia M. Ullman Professor of Ecology in the School of Life Sciences at Arizona State University, was named a 2019 Fellow of the Society of Freshwater Science in honor of her outstanding contributions to stream and watershed science.

According to Grimm's biography on the Society of Freshwater Science fellows site, "Grimm studies urban and stream ecosystems. Initially working on stream nitrogen dynamics, she expanded out and down to riparian and hyporheic zones and then abruptly became an urban ecologist."

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Tempe Town Lake sends message in a bottle

View Source | November 1, 2018

Man and woman standing near lake holding a bottle of lake waterTempe Town Lake has been a part of the city's landscape for over 19 years, and Hilairy Hartnett's lab has been measuring and collecting data there for the past 13.

With over 1,200 samples of water, Hartnett's work with the Central Arizona Phoenix Long-Term Ecological Research Program hopes to better understand what it takes to maintain the ecological health of a man-made lake in one of the hottest regions of the United States.

The associate professor in Arizona State University's School of Earth and Space Exploration and the School of Molecular Sciences spoke with ASU Now about her decade-plus sampling Tempe Town Lake. Read Hartnett's interview on ASU Now.

CAP LTER urban ecology work highlighted by Arizona PBS

View Source | October 15, 2018

2 people making measurements in desert with city skyline in the backgroundThe Central Arizona–Phoenix Long-Term Ecological Research program, a unit of the Julie Ann Wrigley Global Institute of Sustainability at Arizona State University, was recently featured in an episode of “Catalyst” by Arizona PBS. The episode, “Desert animals in urban centers,” discussed current research about how natural environments (including plant and animal life) are affected by urban development.

Sharon Hall, a senior sustainability scientist who works with the CAP LTER, said that some plant and animal life continues to flourish within or nearby Phoenix.

"There's all these hidden spots around the city that nature is thriving,” said Hall. “If we can think about finding those areas and protecting them — or at least understanding them a bit better, maybe then we can try to make our landscape a little bit more friendly to the types of animals that . . . are living among us all the time."

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CAP LTER urban ecology program funded another four years

July 9, 2018

Two researchers stand in mud and hold cameras at Tres Rios, Arizona
Sally Wittlinger and Lindsey Rustad at Tres Rios, Arizona. Photo courtesy of Mark Watkins
For 20 years, Arizona State University’s Central Arizona–Phoenix Long-Term Ecological Research Program has been studying the Phoenix urban ecosystem from a holistic, interdisciplinary and social-ecological perspective. The National Science Foundation has funded CAP through grants since 1997 as part of its national network of 28 LTER sites. Recently, news broke that the fourth phase of CAP research will be fully funded through 2022.

“I was at a remote field camp in South Africa teaching my study abroad program when word came from the NSF that a decision had been made,” said Dan Childers, CAP’s director and School of Sustainability professor. “We didn’t even have cell service where we were, so I called our NSF program officer on a satellite phone. It was wonderful to get this very good news while in such a beautiful place!”

Much of the current CAP research is focused on urban ecological infrastructure, which is effectively everything except the built environment. The overarching goal of the program is to foster social-ecological research aimed at understanding complex urban ecosystems, using a holistic perspective while enhancing urban sustainability and resilience. The CAP research enterprise is organized around eight interdisciplinary research questions and includes nearly 60 ASU faculty from all four campuses, scientists from several other universities, and dozens of students and postdoctoral scholars.

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20th Annual Poster Symposium and All Scientists Meeting

November 17, 2017

Phoenix Night SkylineSave the date! CAP LTER will be holding its 20th Annual Poster Symposium and All Scientists Meeting on January 5th, 2018 at ASU's SkySong facility in Scottsdale. Weiqi Zhou, Professor in the State Key Laboratory of Urban and Regional Ecology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, will be the keynote speaker. Dan Childers will give us an update on CAP LTER and there will be presentations by the leaders of the Integrated Research Teams.

Wisdom from the Director’s Lava Lamp

February 8, 2017

Yellow lava lamp on a table along with a mug and business cardsDear CAPpers:

As we begin a new year, a new phase of CAP, and a strange new world, I have some news and important information to pass along.

First, many thanks to Mark, Cindy, and everyone else who helped make our 2017 All Scientist Meeting such a success. Final head count was more than 100 attendees! I received a great deal of positive feedback about Diane’s excellent and very timely plenary talk, Nancy’s insightful infrastructure talk, and the wonderful collection of fire-talks we had about CAP modelling efforts. The posters were equally impressive.

Speaking of the posters, here are the results of our student poster contest (drumroll, please)... And the Winner of the 2017 CAP Student Poster Contest is Megan Wheeler, who presented “Residential soil water model evaluation to improve outdoor water use recommendations in Phoenix, Arizona” with Sharon Hall and Enrique Vivoni! Congratulations, Megan! You won up to $500 towards your travel to a conference where you present your CAP data!

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Undergraduate research opportunities at LTER sites

January 5, 2016

Searching for black widows at night.The Ecological Society of America's SEEDS initiative, which aims to increase diversity in the field of ecology, is recruiting undergraduate students from underrepresented groups for the SPUR fellowship program. This program places students at ecological research sites across the United States. Several LTER sites are part of the SPUR fellowship program this year: Central Arizona-Phoenix (CAP) LTER, Harvard Forest LTER, Baltimore Ecosystem Study LTER, Cedar Creek LTER, and Kellogg Biological Station LTER. An additional site is the Llado River Field Station in Texas.

Students accepted as SPUR fellows will engage in a research project at one of these research sites under the mentorship of a faculty member, senior graduate student, or post-doctoral fellow. SPUR fellows will receive funding for travel and housing as well as a subsistence stipend.

To view the application requirements and apply, interested undergraduate students should visit the SPUR fellowship page on the SEEDS website. Applications are due January 15, 2016.

High school girls learn coding

November 2, 2015

Highschool Girls Learn CodingA group of high school girls in Mesa Public Schools spent their fall break learning to code in R, a computer language used for statistical analysis. This workshop was the brainchild of Jessica Guo, a CAP graduate student, who is passionate about coding and determined to bring more girls into STEM (science, technology, engineering, and mathematics). A graduate of Mesa Public Schools herself, Jessica is part of the ASU/NASA Space Grant program.

In the workshop that Jessica led, girls accessed large, publicly-available datasets and used coding to analyze the data and to create graphs, which they presented to their peers. Among the datasets that the girls used were ones created by LTER Network sites.

CAP Co-Sponsors Light Pollution Conference

October 7, 2015

IDALight pollution is a critical ecological issue in the city, which has gotten little attention. CAP is co-sponsoring the International Dark Sky Association’s (IDA) annual meeting in Scottsdale, November 14-15, which is focusing on "Impacts of Artificial Night Lighting on Fish and Wildlife Resources and the Mitigating Role of Emerging Lighting Technologies.” IDA advocates for the reduction of light pollution and promotes the use of lighting products that have lesser impacts on biota and the environment.


Trees and lawns curb excessive urban heat

October 7, 2015

A recent ASU News article on the role of trees and lawns in urban heat island featured CAP scientists Ben Ruddell, Ariane Middel, and Nancy Selover. Shade provided by trees has been long acknowledged as providing some relief from high daytime temperatures in the Valley of the Sun. The team of ASU scientists has worked to quantify the effects of different types of shade on urban microclimates and how much shade is needed to reduce daytime temperatures. This is very useful information for homeowners, designers, architects and others wanting to know just how much shade they need.

SESYNC-LTER Postdoctoral Fellowships

October 7, 2015

Attention all Post-docs! Looking for a LTER fellowship? Apply for a two year postdoctoral fellowship today with The National Socio-Environmental Synthesis Center (SESYNC) in collaboration with the National Science Foundation's Long Term Ecological Research (LTER) program beginning August 1st, 2016.

-Prescreening application deadline is October 26, 2015, 5 p.m. Eastern Daylight Time (EDT).

-Collaborating Mentor application deadline: October 26, 2015, 5 p.m. Eastern Daylight Time (EDT).

-Collaborating Mentor selection and commitment deadline: November 16, 2015, 5 p.m. Eastern Standard Time (EST).

-Fellowship application deadline: December 7, 2015, 5 p.m. Eastern Standard Time (EST).

Click here to find more information on SESYNC-LTER and the fellowship criteria.

Director Notes June 2015

June 12, 2015

Nancy GrimmDear CAP Colleagues, Students, and Friends,

We’re heading into summer with some exciting synthesis research funded and underway! Several groups of CAP scientists will analyze long-term data to address specific scientific questions. We expect these projects will contribute greatly to the development of the CAP-IV proposal. 

The projects and teams are:

  • Using the Survey 200 data to discern influences of climate, plant communities, and land use on decadal patterns of soil properties (Becky Ball and Sharon Hall)
  • Studying the structure of food webs and biodiversity patterns, and how they change with land use and climate anomalies (Dan Allen, Heather Bateman, Chris Martin, John Sabo, Jean Stutz, Albert Ruhi)
  • How has urbanization in riparian zones on two major streams affected ecosystem service provision? (Dan Allen, Ben Ruddell, Nancy Grimm, Billie Turner, and Xiaoxiao Li)
  • Using long-term land cover data to understand how metrics of spatial patterning have changed (WenWen Li and Libby Wentz)
  • Statistical synthesis of long-term climatic and land use/land cover datasets (Zhihua Wang and Soe Myint)
  • Relating long-term changes in urban biodiversity with changes in human perception and management (Paige Warren, Kelli Larson, Heather Bateman, Susannah Lerman, Sharon Hall, Christofer Bang)
  • Determining residential landscaping water requirements in the CAP ecosystem using a water balance model and long-term, experimental yard datasets (Sharon Hall, Enrique Vivoni, and Kelli Larson)
  • Synthesis of longitudinal land cover analysis and long term social and environmental trends (Ray Quay, Sharon Hall, Sharon Harlan, Billie Turner, Kelli Larson, Ben Ruddell, Yujia Zhang, and Xiaoxiao Li)
  • Time-series analysis of Tempe Town Lake biogeochemistry (Hilairy Hartnett, Monica Palta, and Albert Ruhi)
  • Impacts of haboobs and dust storms on the chemistry of Tempe Town Lake, bringing together long-term datasets on atmospheric and aquatic chemistry (Hilairy Hartnett and Pierre Herckes)

In addition, we have five graduate student projects funded through our Grad Grants program, which will also contribute to the corpus of research syntheses we have to work with as we gear up for the renewal. Congratulations to these graduate students:

  •  Chao Fan – developing new analytical tools to describe urban sprawl and exploring its relationship with the urban heat island
  • Ben MacNeille –bacterial communities of the phyllosphere and their mitigation of atmospheric pollution
  • Julie Ripplinger – Bottom up and top down social and ecological controls of residential plant communities, using Survey 200 data
  • Melinda Weaver – how urban stresses alter behavior of house finches
  • Qunshan Zhao – relationship of urban heat island to roof materials

    Research in residential landscapes is a key components of CAP's urban ecology research program
    Stevan conducting fieldwork!

Since my last note, a lot has happened – especially comings and goings. Stevan Earl has stepped down as CAP Site Manager, assuming a position as Data Manager for GIOS. In that capacity, he will continue to work with CAP scientists on getting their data into the database (please put your data into the database!). We welcome Sally Wittlinger, as of May 18, as our new Site Manager! Sally brings a wealth of experience in program and lab management and comes to us most recently from DCDC. Look for a more thorough introduction after she begins work. Our CAP student worker, Mary Munoz Encinas, is graduating from ASU in a few days. Mary has been behind the scenes entering biota data as well as completing her own work using our urban shade tree data.Congratulations to Mary!

Here are some additional CAP LTER highlights:

  • We had another very successful and well-attended All Scientists meeting in January, with Kathy Jacobs (formerly Director of the National Climate Assessment and now Director of the UA’s Center for Climate Adaptation Science and Solutions) as our keynote speaker and a distinguished panel discussing the future of Phoenix.
  • Planning for the CAP-IV proposal is well underway with Dan Childers at the helm.
  • Survey 200 is well underway. We are especially grateful to Lindsey Pollard, who stepped in when Stevan moved to the IT group to ably coordinate the survey.
  • Dr David Hulse visited ASU to deliver a special CAP seminar on his excellent work on future scenarios for the Willamette River Basin in Oregon.
  • Congratulations to Tony Brazel and Kerry Smith, who were awarded CAP LTER research awards and were honored at a small gathering in April.
  • ASU is a recommended recipient of two of the three Sustainability Research Networks (SRN) awards (expected start in late summer/early fall). ASU is the lead institution of the first, the Urban Resilience to Extremes (UREx) SRN (Charles Redman, PI, Nancy Grimm and Mikhail Chester, co-PIs), and is a subawardee for the Urban Water Innovation Network (U-WIN) SRN led by Colorado State (Matt Georgescu, co-PI). Both proposal strongly leveraged CAP. However, both are pending at this writing!
  • CAP recently submitted an equipment proposal to replace a vehicle and partially support the acquisition of a new gas chromatograph for trace-gas analysis.
  • CAP (Phoenix) is again on the drawing board as a potential urban ‘relocatable’ site for NEON – stay tuned.
  • Since last writing, three graduate students affiliated with CAP have or are in the process of defending their dissertations/theses. Join me in congratulating the following:

    • Thomas Bleasdale defended his dissertation, “Gardens of justice: Food-based social movement in south and west Phoenix,” on April 16th (Sharon Harlan, Chair; Bob Bolin and Kevin McHugh, committee members)
    • Hannah Heavenrich will defend her thesis, “Soil biogeochemical consequences of a ‘sustainable’ urban grassland to shrubland transition,” on May 13th (Sharon Hall, Chair; Kelli Larson and Diane Pataki, committee members)
    • Jeffrey Ackley will defend his dissertation, “Rich lizards: How affluence, land cover, and the urban heat island effect influence desert reptiles persisting in an urban landscape,” on May 15th (Jianguo Wu and Brian Sullivan, co-chairs; Soe Myint, Dale Denardo, and Michael Angilletta, committee members)

  • CAP REU student, Jessica Jia, successfully defended her Honor’s Thesis, “Quantifying the trade-off between landscape vegetation height, surface temperature, and water consumption in single-family residential houses for a desert city,” this spring (Kelli Larson and Elizabeth Wentz, co-chairs). Congrats to Jessica as well!

 A little news about me: Although I will be taking sabbatical during the 2015-2016 academic year, I will mostly be here (staybatical) and will continue to lead CAP in collaboration with Dan, as we begin the process of transitioning leadership. I will also be very busy helping to get the new UREx SRN project underway. In June, I will spend a week at Kellogg Biological Station (one of our sister LTERs) as an ‘eminent ecologist’ (their title) in residence. I will spend a bit of time in New Mexico throughout the year, and have plans for a 4-6-week stay in Stockholm at the Resilience Center late next spring. But I will be completely available for all things CAP, so send me email or give me a call at any time.

Finally, congratulations and thanks go to the authors of the 18 journal articles that have appeared since my December update. These papers are listed below. Please do let us know if we’ve missed any, and as always, remember to keep Cindy and Marcia informed of new journal articles, book chapters, books, or noteworthy presentations—and to acknowledge CAP in your publications.

I wish each of you a productive and relaxing summer.



Publications since my December 2014 Director Note:

Abbott, J. K., H. A. Klaiber and V. K. Smith. 2015. Economic behavior, market signals, and urban ecology. NBER Working Paper Series, Working Paper 20959. (link)

Ackley, J. W., M. J. Angilletta Jr., D. DeNardo, B. Sullivan and J. Wu. 2015. Urban heat island mitigation strategies and lizard thermal ecology: Landscaping can quadruple potential activity time in an arid city. Urban Ecosystems DOI: 10.1007/s11252-015-0460-x. (link)

Ackley, J. W., J. Wu, M. Angilletta, S. W. Myint and B. Sullivan. 2015. Rich lizards: How affluence and land cover influence the diversity and abundance of desert reptiles persisting in an urban landscape. Biological Conservation 182:87-92. DOI: 10.1016/j.biocon.2014.11.009. (link)

Bestelmeyer, S. V., M. M. Elser, K. V. Spellman, E. B. Sparrow, S. S. Haan-Amato and A. Keener. 2015. Collaboraton, interdisciplinary thinking, and communication: New approaches to K-12 ecology education. Frontiers in Ecology and the Environment 13(1):37-43. DOI: 10.1890/140130. (link)

Childers, D. L., M. L. Cadenasso, J. M. Grove, V. Marshall, B. McGrath and S. T. Pickett. 2015. An ecology for cities: A transformational nexus of design and ecology to advance climate change resilience and urban sustainability. Sustainability 7(4):3774-3791. DOI: 10.3390/su7043774. (link)

Gifford, M., J. Liu, B. E. Rittmann, R. Vannela and P. Westerhoff. 2015. Phosphorus recovery from microbial biofuel residual using microwave peroxide digestion and anion exchange. Water Research70:130-137. DOI: 10.1016/j.watres.2014.11.052. (link)

Ibes, D. C. 2015. A multidimensional classification and equity analysis of an urban park system: A new methodology and case study application. Landscape and Urban Planning 137:122-137. DOI: 10.1016/j.landurbplan.2014.12.014. (link)

Marusenko, Y. Y., F. Garcia-Pichel and S. J. Hall. 2015. Ammonia-oxidizing archaea respond positively to inorganic nitrogen addition in desert soils. FEMS Microbiology Ecology 91(2):1-11. DOI: 10.1093/femsec/fiu023. (link)

McHale, M., S. Pickett, O. Barbosa, D. Bunn, M. Cadenasso, D. Childers, M. Gartin, G. Hess, D. Iwaniec, T. McPhearson, M. Peterson, A. Poole, L. Rivers, S. Shutters, and W. Zhou. 2015. The new global urban realm: Complex, connected, diffuse, and diverse social-ecological systems. Sustainability 7: 5211-5240. (link)

Metson, G. S., D. M. Iwaniec, L. A. Baker, E. M. Bennett, D. L. Childers, D. Cordell, N. B. Grimm, J. M. Grove, D. A. Nidzgorski and S. White. 2015. Urban phosphorus sustainability: Systematically incorporating social, ecological, and technological factors into phosphorus flow analysis.Environmental Science & Policy 47:1-11. DOI: 10.1016/j.envsci.2014.10.005. (link)

Rudd, B. T. and H. L. Bateman. 2015. Reptile use of trails in the Phoenix mountain parks. Herpetological Review 46(1):15-17.

Shaffer, S. R., W. T. Chow, M. Georgescu, P. Hyde, G. D. Jenerette, A. Mahalov, M. Moustaoui and B. L. Ruddell. 2015. Multiscale modeling and evaluation of urban surface energy balance in the Phoenix metropolitan area. Journal of Applied Meteorology and Climatology 54:322-338. DOI: 10.1175/JAMC-D-14-0051.1. (link)

Shuster, W. D., S. D. Dadio, C. E. Burkman, S. R. Earl and S. J. Hall. 2015. Hydropedological assessment of parcel-level infiltration in an arid urban ecosystem. Soil Science Society of America Journal Open Access. DOI: 10.2136/sssaj2014.05.0200. (link)

Volo, T. J., E. R. Vivoni and B. L. Ruddell. 2015. An ecohydrological approach to conserving urban water through optimized landscape irrigation schedules. Landscape and Urban Planning 133:127-132. DOI: 10.1016/j.landurbplan.2014.09.012. (link)

Wang, Z. H. 2014. A new perspective of urban-rural differences: The impact of soil water advection. Urban Climate 10: 19-34. (link)

Wang, Z. H. 2014. Monte Carlo simulations of radiative heat exchange in a street canyon with trees. Solar Energy 110: 704-713. (link)

White, D. D., A. Y. Wutich, K. L. Larson and T. Lant. 2015. Water management decision makers’ evaluations of uncertainty in a decision support system: The case of WaterSim in the Decision Theater. Journal of Environmental Planning and Management 58(4):616-630. DOI: 10.1080/09640568.2013.875892. (link)

Yang, J., and Z. H. Wang. 2014. Physical parameterization and sensitivity of urban hydrological models: Application to green roof systems. Building and Environment 75: 250-263. (link)