Biography

My research explores the intersection of the history of human societies and Earth's climate history during the Holocene. From the economic and legal records of the Ptolemaic dynasty to volcanic impacts on the Nile River revealed through polar ice cores, my work shows how environment and society shaped one another. What began as a fascination with history during my childhood has grown into a broader pursuit: understanding how climate and human resilience are intertwined across time.

On a bright, clear Spring morning in April 2016, with the distant Sierra Nevada mountains gleaming with snow and ice, I walked up the steps and through the doors of the Desert Research Institute (DRI) for the first time.

Of the many places I’ve visited, the Alaska Range, the Andes, the Eastern Desert in Egypt, the Icelandic interior, I never thought my most profound epiphany would occur in Reno, Nevada. I thought of it as a rough, gambling town, a minor league version of its sister city to the south, and it didn’t even have the Hoover dam as an attraction. How quickly experience can overturn prejudice! Reno is now one of my favorite destinations, and, as it turns out, walking through those doors was not the beginning but the end point of a journey that I had begun decades earlier and far from the mountains.

I grew up in the near western suburbs of Chicago, and I was quite fortunate to watch some very good children’s television shows before school. I was especially fond of “Garfield Goose and Friends.” One of the show’s regular features was a serialized English language version of the Czech film Journey to the beginning of time (originally 1955, in the US 1966). I was captivated. In the American version of the film, four young boys began their journey by walking across the Queensboro Bridge into Manhattan, ending up at the American Museum of Natural History on the Upper West Side.

After wandering through a hall devoted to early Alaskan peoples, the boys encounter dinosaur skeletons in Jurassic Hall and are awestruck by the T. Rex. The young scientist of the group explains Earth’s geological ages and evolutionary history with the observation that “the further back in time the simpler life becomes.” After several hours and two trips through the rooms, the boys, ready to do something else, leave the museum. They head out into the lake in Central Park, reach a cave, and bravely continue rowing. Everything changes once they are out in daylight on the other side. They had somehow rowed into “a whole new world”— the lake in Central Park had become a semi-frozen river, a river of time. The air was colder, glaciated peaks were all around them; they had entered the last ice age. Moving back in time as they rowed, they encounter an “elephant.” But it was no elephant, it was a mammoth.

I watched as the four boys proceeded to have a series of adventures, observing megafauna, evidence of early humans, taking notes as they kept rowing further back in time from the Pleistocene into the Tertiary, noting changes in climate from cold to warmer conditions, different flora and fauna as the Earth’s climate changed, into the Mesozoic and all the way back to the Precambrian age. The “spectacle of life” evolved backward through time all the way to the beginning of creation. The film ends with the boys back at the Museum wondering if it had all been a dream. Except the well-worn and soaking wet diary that the boys kept suggests otherwise.

It was a clever film, science as adventure of the best kind. But it made a more profound, subtle point: we are connected through space and time to a deep history of life on Earth. The film made an enormous impression on me, ending with the question, “can we project ourselves back in time?” That filled me with a sense of wonder and, I now know, played a role in guiding me toward making my life’s work the study ancient history. I was in Reno because in a very real way, science has figured out how to project us back in time for real.

From History to Climate Science

My childhood fascination with ancient Egypt captured my imagination early. My favorite book growing up, and I’ve read it cover to cover several times over the years, was James Henry Breasted’s A History of Egypt (1909). Breasted was the founder of the Oriental Institute at the University of Chicago, and the Institute became a place of pilgrimage for me, and eventually the site of my graduate studies. Like other historical surveys, Breasted’s first chapter was dedicated to “The Land”—climate, temperature, and above all the Nile River and its annual flood. It was a poetic evocation of the Nile valley and the civilization that grew up along the river, but it was mere scene-setting, an obligatory yet vague nod to the riverine environment before getting to the political, social, cultural, and military events of Egypt.

I became increasingly fascinated with studying Egypt, but when I reached college, I knew I wanted to broaden my horizons by studying History and the History of Art. Still, science lurked. My first declared major was Biophysics, but I didn’t yet know how to combine science and History.

My graduate work focused on the Ptolemaic dynasty, the last ruling dynasty of ancient Egypt, and it demanded that I learn the fascinating, if challenging, demotic Egyptian cursive script so I could read the thousands of economic and legal records that survive in that language. For several years I focused on the economic and legal history of Ptolemaic Egypt. It is a subject that still fascinates me.

My broader research interest was in how societies worked. And that interest is what led me to climate science, a field only decades old.

A few years ago, I organized a conference on revolts in the ancient world, focusing on a sequence of social disturbances well documented from Ptolemaic records. For several years, I had sensed that work on understanding past climate was advancing rapidly, perhaps in ways that would shed light on Ptolemaic Egypt. At a congenial dinner in New Haven before the conference, my historical interests and my renewed interest in science collided head-on. A climate historian, and now friend and project partner, Francis Ludlow, showed me how ice core geochemistry could now more accurately help to date and locate large volcanic eruptions. For the first time I saw with causal clarity how short-term climate change could contribute to societal distress.

I had always understood that Nile River flooding had shaped Egyptian history in fundamental and important ways. The fifth century BCE Greek historian Herodotus long ago told us that Egypt was the “gift of the river.” This was reinforced when I read during my first week of graduate school Karl Butzer’s classic Early Hydraulic Civilization in Egypt.

Not often read now, it remains a great book. It convinced me that Egyptian history was more about the annual flood of the river and agriculture than it was about Tutankhamun’s tomb or Karnak temple, as magnificent as both are. Butzer’s book had lodged deep into the recesses of my mind. Nile flood variability was an important aspect throughout Egyptian history. So, when Francis showed me the new chronology of the volcanic eruptions to be published in Nature in 2015, it took me right back to Butzer. But instead of seeing Nile River fluctuations over one or two centuries, I thought, maybe we could get an understanding of the river in more detail. And what did volcanoes have to do with anything anyway? That set me on the road to Reno.

A Laboratory for Time Travel

The Desert Research Institute was founded in the same year I was born. Nestled in a stunning part of the Sierra Nevada foothills that divide California and Nevada, down a long, narrow corridor, is the Trace Chemistry/ Ice Core lab of Joe McConnell. It is an innocuous sounding, tiny suite of rooms. But to enter the lab is to journey back in time. You will see on your left side a series of computer monitors, graphs recording data rising up and down like a slow heartbeat, some of the screens showing live shots of the “cold room” where ice cores are prepped and then melted for analysis. It is the cutting edge of climate science.

Ice cores have been called a “two-mile time machine,” referring to the deepest ice core ever drilled in Antarctica that goes back almost one million years into Earth’s past climate. [1] And ice cores, and other historical climate records, have been a critical part of understanding climate change.

McConnell’s lab has been a pioneer in ice core research since the 1970’s, playing an important role in the first continuous ice core drilling and analysis of one of the important ice core projects that I’ll touch on in the next chapter, the Greenland Ice Sheet Project. There are four small rooms: a basic lab space, a cold lab for the storage and the preparing and melting of ice cores, a wet chemistry lab with a row of computer screens and a bench the supports delicate instruments, and, sealed off from the other rooms, a clean room which houses two HR-ICP-MS’s. These High Resolution Inductively-Coupled Plasma Mass Spectrometers (I throw this term around at parties now), developed in the 1980’s, have now become essential tools for climate scientists who are trying to reconstruct past climatic conditions around the world

[1] Richard B. Alley, The Two-Mile Time Machine. Ice Cores, Abrupt Climate Change, and Our Future. Princeton:Princeton University Press, 2000. The longest continues ice core so far is the “Beyond Epica” core that drilled down 2800 meters that extends back almost 1.2 million years. The project promises much exciting new data as it began June 14, 2025. https://www.beyondepica.eu/en/