Don Pierson

My research deals with the interactions between climate, watershed hydrology, and lake ecosystems. In particular how these interactons are changing as a result of global warming To better evaluate such interactions I make use of automated lake monitoring systems, and Lake modeling simulations. I work both at the Department of Limnology in Uppsala and the Erken Laboratory in Norrtälje.

Overview

My research involves quantifying the effects of environmental variability on lakes that result in variations in thermal structure light climate, nutrient inputs, and ultimately lake ecology. I am interested in the coupling of lakes to their watersheds and how variations in climate affects this. For example, how climate simultaneously affects the watershed processes that affect the seasonality of streamflow and the timing and pattern of lake thermal structure that affect the transport of the materials entering from the watershed.

Ongoing climate change influences all of these processes, and much of my research is involved in evaluating the effects of climate change on lakes. I have worked on some of the first projects to evaluate the effects of climate change on European lakes, and when not working at Uppsala University I have been the section chief for Water Quality modeling for the New York City Water Supply. There, building on our experience in Europe, we initiated the NYC Climate Change Integrated Modeling Project one of the first long term evaluations of the effects of climate change on a major water supply in the United States. (http://www.nyc.gov/html/dep/html/about_dep/climate_resiliency.shtml)

To better understand climate-lake interactions I have developed an expertise in automated lake monitoring systems. Starting in 1986 as a PhD student I began working with the monitoring program at Lake Erken – automating collection of lake meteorological data and developing systems to measure lake water temperature at high temporal and vertical resolution. As a consequence, Lake Erken now has one of the longest records of such data in Europe. I now work part time at the Erken Laboratory (http://www.ieg.uu.se/erken-laboratory/) developing and expanding automated monitoring systems and making these data more widely available through the Swedish Infrastructure for Ecosystem Science – SITES network (http://www.fieldsites.se/). I have also been a long-term participant in the Global Lakes Ecological Observatory – GLEON network (http://www.gleon.org/) and the Networking Lake Observatories in Europe Network (https://www.dkit.ie/networking-lake-observatories-europe)

As we measure at higher frequency and in a continuous and consistent manner with the help of automated systems we are becoming more and more aware of the fact that change to aquatic systems is not gradual, but instead is the consequence of episodic events. These events occur along a continuum in magnitude from wind gusts to hurricanes, but have the common characteristic of having an effect that persists longer than the event itself. We are presently mining the long-term records from Erken and other sites in Europe to gain a better understanding of the effects of episodic events on the thermal structure and ecology of lakes.

In the past I have lead research project that developed remote sensing methods that could be applied to inland water bodies. As a consequence of this experience and that of working for the New York City water supply I have a knowledge and appreciation of applied limnological research to support the management of water resources.

Current Projects

I am currently involved in two European Union Funded Projects described below. I am the consortium coordinator of the PROGNOS project which is funded by the European Union Water JPI program. I am also a participant in the Marie Sklodowska-Curie Innovative Training Networks European Joint doctorate project MANTEL, which will train a group of 12 PhD students in a consortium of 8 Universities and 14 additional partner organizations. I will jointly supervise two PhD students, who will be using lake modeling methods to evaluate the effects of episodic events.

PROGNOS - Predicting In-Lake Responses to Change Using Near Real Time Models (http://prognoswater.org/)

Lakes and reservoirs are under continuous pressure from urbanization and agricultural intensification, and from changes in climate, including an increasing occurrence of extreme climatic events. These pressures can reduce water quality by promoting the occurrence of nuisance algal blooms and higher levels of dissolved organic carbon (DOC), two issues that can substantially increase the costs for water treatment. To monitor such changes in water quality, automated high frequency (HF) monitoring systems are increasingly being adopted for lake and reservoir management across Europe. These HF data are mostly used to provide near real time (NRT) information on the present lake state. An even more valuable tool for water management, however, would be to use HF data to run computer models that forecast the probability of a change in lake state in the coming weeks or months. In PROGNOS, we will develop an integrated approach that couples HF lake monitoring data to dynamic water quality models to forecast short-term changes in lake water quality. This will potentially provide a greater window of opportunity over which to make water quality management decisions, and will increase the value of HF monitoring data, ensuring that their potential to guide water quality management is fully realized. This project will promote innovative solutions for water-related challenges across Europe. It will develop, demonstrate and disseminate forecast based adaptive management solutions for two specific water quality threats: nuisance algal blooms and the production disinfection by-products from DOC. The technology demonstrated here has the potential to transform water management and foster the growth of European companies that specialize in adaptive water management and water quality forecasting systems. The project consortium includes expertise from European sites that have been involved in the forefront of HF monitoring systems since the late 1990s, expertise in modelling algal blooms and DOC levels, and expertise in assessing societal benefits from changes in water management.

MANTEL - Management of Climatic Extreme Events in Lakes Reservoirs for the Protection of Ecosystem Services

Environmental perturbations to lakes and reservoirs occur largely as episodic climatic events. These range from relatively short mixing events to storms and heat waves. While the driving events occur along a continuum of frequency and magnitude, however, their effect is generally longer lasting than the events themselves. In addition, the more extreme weather events are now becoming increasingly frequent, a trend that has been linked to directional climate change and is projected to continue in the coming decades. Understanding the impact of these short-lived pressures requires monitoring that captures the event (hours–days) and the ensuing impact, that can last for months or even years. Only recently has automated high frequency monitoring (HFM) of lakes been adopted throughout Europe. This Training Network will investigate the effects of the most extreme events, and of cumulative lower magnitude events, using HFM, while at the same time training a cohort of doctoral students in state-of-the art technology, data analysis and modelling. The aim of the EJD is to change the way in which water quality monitoring is carried out so that the effects of episodic climatic events can be understood, thus ensuring that future water management strategies can explicitly account for their effects.