Climatology

Although I grew up in Minnesota, I developed a deep passion for the ocean during childhood snorkeling trips within the Buck Island Reef National Monument in St. Croix, US Virgin Islands (USVI).  I attended Florida Institute of Technology and graduated summa cum laude with a Bachelors of Science in Marine Biology in the spring of 2006.  At FIT, I played Division II softball for two years and was an All-American Scholar Athlete both years. I was also involved in undergraduate research under Dr. Robert van Woesik, modeling the timing of coral bleaching and coral spawning events.  In the spring of 2006, I was named FIT's Outstanding Senior of the year.

I continued working under Dr. van Woesik at FIT, earning my Masters of Science in Marine Biology in the spring of 2008.  My thesis researched focused on the relationship between the frequency of thermal stress events in the past and the severity of coral bleaching during recent warm periods.  During my masters research, I realized how little we understood about one of the main drivers of coral bleaching, the El Niño-Southern Oscillation (ENSO) climate system.  Realizing that we ultimately need a better understanding of how tropical climate variability will change in the future in order to predict the severity of future bleaching events, I became interested in studying climate variability from the natural archive that coral reefs provide.

Understanding the effects of climate change on ENSO is crucial for regional climate and coral bleaching predictions, because ENSO events drive intense floods, droughts and temperature anomalies all over the world.  To improve our understanding of the effects of natural and anthropogenic warming on the magnitude of the Pacific-SST gradient and the strength of ENSO during the last century, I aim to extend the network of high-resolution modern coral and lake sediment records from the tropical Pacific Ocean.  As part of my dissertation research, I am developing replicated temperature and salinity records from cores of modern corals from the central and eastern Pacific Ocean [Onotoa Atoll (1º50'S, 175º30 'E), Maiana Atoll (1ºN, 173ºE), Jarvis Island (0.36ºS, 159ºW), and Wolf Island, Galapagos Archipelago (1.67ºN, 91.9W)].  To address longer-term variability in the tropical Pacific over the Holocene, I am also analyzing a lake sediment core from Bainbridge Crater Lake, Galapagos (0°21'S, 90°34'W).  To improve our understanding of how climate anomalies, such as those experienced during El Niño events, are recorded in Bainbridge Crater Lake, we have also been monitoring the local climate, limnology and sedimentation of the lake since the winter of 2009.  Finally, to address possible future projections for the tropical Pacific, I have used a simple forward model of coral proxy records to assess CGCM hindcasts.

Primarily climate change in the tropics.

I am a graduate student in the Enquist lab at the University of Arizona. I am interested in the dynamics and statistical properties of biological networks. I am also interested in improving K-12 science education through experiential approaches.

I grew up in Tucson, Arizona, watching monsoon thunderstorms sweep across the Tucson basin every summer. This childhood experience prompted me to pursue meteorology until an interdisciplinary environmental science program at Stanford made me realize that climate – specifically paleoclimate and how past climate changes have affected humans – is where my interests lie. 

Now, my research explores the dynamical mechanisms of the North American monsoon over the Holocene (last 10,000 years). The North American monsoon delivers half of our annual precipitation, but it is currently a feature of Southwest hydroclimate that is not well reproduced in global climate models. Thus, we do not know if we should prepare for major changes in the monsoon as climate changes – what if it fails, as it did in the summer of 2009 when we got only a few weeks of rain, for a number of years in a row?  What does that mean for water managers and residents of the Southwest?

With those questions in mind, I am reconstructing the range of monsoon variability on a variety of timescales (interannual to millennial). I use lake sediments and cave speleothems to achieve this. Lakes respond to changes in hydrologic balance in a variety of ways (lake level, chemistry, etc), and isotopes in cave speleothems can be used to determine the winter to summer rain balance to the cave site over short (10yr) to long (100,000yr) timescales.

Furthermore, we do not yet fully understand the response of the monsoon to changes in forcings, such as sea surface temperatures of nearby ocean basins, atmospheric conditions, El Niño, or changes in radiative forcing (increased solar insolation in the past, or increased greenhouse gas concentrations in the present). Thus, by targeting time periods in the past where we know these conditions were different than they are today, we can hope to develop more reliable projections of summer rain in the coming years to decades as these forcings change. Understanding the variability inherent in the monsoon system is critical to preparing for future changes in water availability in southern Arizona and Mexico.

Another project I am currently undertaking is designed to understand speleothems as “sensors” of climate. In many monsoon regions of the world, oxygen isotopes in speleothems are taken to represent the monsoon strength over longer timescales. However, in the desert Southwest, we get two pulses of rain each year, one during the winter and one during the summer. This complicates matters somewhat. Therefore, I am monitoring a number of Southern Arizona caves monthly to determine how calcite formation and dripwater isotope geochemistry relate to interannual climate variability. This, in conjunction with simple hydrological flow modeling, will hopefully help clarify what specific geochemical changes in speleothems signify in terms of climatic change over the past few thousand years.

I am also increasingly interested in science communication. Recent public controversy over the email hack of the Climate Research Unit at the University of East Anglia has illustrated that there exists a gap between climate science and the public’s understanding thereof. I am working with a few other students here to develop better methods and avenues of communication with the public, in the hopes of avoiding miscommunications as seem to happen all the time. I hope to combine these interests during my tenure in graduate school and in the future. 

I am an environmental scientist working on issues of climate, water, hazards, and natural resources management. A Ph.D. candidate at the University of Arizona in Tucson, I am majoring in Geography and minoring in Global Change. My mentor and advisor is Dr. Connie A. Woodhouse. My research appointment is with the Laboratory of Tree-Ring Research. I am affiliated with the Climate Assessment for the Southwest and the UA Institute of the Environment. My graduate studies are supported by a U.S. EPA STAR Fellowship.