Insofar as hydrology is the study of the distribution and movement of water, ecohydrology, at its simplest, studies how water’s distribution affects ecosystems and vice versa how ecosystems affect water. That is reductionistic, but I take a very broad view of this definition – soils, the atmosphere urban landscapes, anthropenic influences, etc fit into ecohydrology as well. Perhaps more broadly, I think of ecohydrology as a relatively interdisciplinary study of how water, plants, and living things all are coupled and affect each other in multiple, usually interactive, ways.
What are your undergraduate and graduate degrees in?
I have an undergraduate degree in Civil and Environmental Engineering from MIT, a MS in environmental science from Duke University, and my PhD is also in environmental engineering from MIT.
How did you arrive at working in/thinking about ecohydrology?
I studied environmental engineering as an undergraduate after getting disillusioned from my original physics major. At the time, hydrology seemed to me to be the most ‘physics-y’ corner of environmental engineering…but a few years of undergraduate study later, I found myself wishing I knew more about the biological aspects of plants and how that would affect my view of what hydrology was. I spent a few fun years working with Gaby Katul at Duke on a variety of projects across hydrologic fields. While I didn’t think of myself as doing ecohydrology at the time, I absorbed some of the great ecohydrological thinking being done around me in the Nicholas School of the Environment. However, I really missed Cambridge and Boston, so I returned to MIT after a few years. After a PhD with Dara Entekhabi that was largely focused on my first love of microwave remote sensing, I’ve enjoyed bringing my fascination with plants back and applying the tools of remote sensing to various ecohydrological problems.
What do you see as an important emerging area of ecohydrology?
Alfredo Huete answered similarly a few months ago, but one exciting emerging area is the use of all the new satellite data that are starting to come online. That includes totally new types of data from new flagship NASA sensors like GEDI, (canopy height and biomass), TROPOMI (solar-induced fluorescence), SWOT (surface water extent and estimates of discharge), or even ECOSTRESS (land surface temperature and thus, estimates of ET). Cubesat data at few-meter resolution have also become dramatically more available in recent years. This is all very exciting and there is lots of great science to be done. But there is such a rapid increase in data availability that we will need to develop new ways of interacting with and analyzing this exponential increase in data. It will be important to learn from ‘big data science’ while still saying grounded in biogeophysical understanding. While doing so, as a community, we will especially have to reckon with the fact that we have a wealth of remote sensing observations about aboveground processes, but that belowground process remain mostly unseen by satellites.
Do you have a favorite ecohydrology paper? Describe/explain.
This feels like picking the best day I’ve ever had. There are so many great ones. I honestly can’t pick a single most favorite, but I’ll highlight a relatively recent one that I really like and isn’t as commonly appreciated: Crow et al’s 2015 GRL paper: “Robust estimates of soil moisture and latent heat flux coupling strength obtained from triple collocation”. This paper modifies a technique known as ‘triple collocation’ to figure out how strongly coupled soil moisture and evapotranspiration are across different Fluxnet sites….but with a careful accounting for the unknown random errors in measurements that turn out to distort a naïve calculation of correlations. It’s extremely elegant and satisfying.
What do you do for fun (apart from ecohydrology)?
I am glad this question points out that ecohydrology *is* a lot of fun! I also try to regularly participate in outdoor activities: hiking, biking, and occasionally climbing. But mostly I spend a lot of time with friends and family. Like many junior faculty at Stanford, I live on land leased from the university to reduce costs in the expensive Silicon Valley area. That feels a bit strange philosophically, but a positive side effect is that many of our closest friends live only about a minute’s walk away – making it easy to spend time with a close community.