Sunday, October 14, 2012

Galápagos Adventures

Weather monitoring at one of our sites
by Jessica Conroy
Hello from the Galápagos, where I’m in the midst of the second leg of my water-sampling journey, following my adventures in Kiritmati last May.  Again I’ve hitched a ride on a paleoclimate project, this time with my graduate advisor, Jonathan Overpeck, long-time collaborator and mentor, Julie Cole, and UA graduate student and good friend Diane Thompson (who you may remember from Kiritimati). It’s a great group, and we’re doing some really exciting science!

I have been working in the Galápagos since I was a baby graduate student, back in 2004. My ultimate goal is to try to understand long-term climate change and climate variability in this region.  There are very few climate observations, like precipitation and temperature, for the 20th century from the Galápagos. Thus, we don’t know much about long-term changes in climate here. And it’s important to understand how 20th century climate was different (or similar?) to past climate, since what goes on in the tropical Pacific can ripple across the atmosphere, influencing climate in many parts of the world.

About to begin the climb down to Genovesa Crater Lake
My graduate work focused on finding the climate signal in Galápagos lake sediments. I’ve found that I can match my more recent lake sediment measurements to the limited climate measurements in the region over the last 50-100 years. This is a super cool approach, not always done in the field of lake science, that can really enhance our understanding of the climate histories we reconstruct from lake sediments—less arm-waving, you could say. But, many questions and uncertainties remain, and there is much more work to be done.

La Pirata, our home for the week.
My postdoctoral work takes up the challenge of better understanding climate signals in lake sediments and in other paleoclimate proxies, like corals. I’m focused on understanding the links between the stable isotope values in seawater and rain and local and large-scale climate. 

 This means I’ve been taking lots of water samples all around the Galápagos—off our awesome boat, La Pirata, from the black shorelines of volcanic rocks, and from some pretty sweet beaches. Life is tough.

Trying to stay clean at El Junco, an unlikely prospect.
Unlike Kiritimati, it’s barely rained here, since it’s the peak of their dry season. However, we did notice as we ventured to a special lake called El Junco into the cloud-covered highlands that it was wet wet wet, with lots of mud to go along with all the misty rain. It was wetter in the highlands than last time I was at El Junco, in 2004. Is this part of a trend? Or just the interannual variability at this elevation? Hopefully I’ll have a good answer to that question soon!