Thursday, April 4, 2013

Hello from Southern California!

by Pamela Grothe

Not all trips in the Cobb lab are to exotic places, but we still travel to cool places nationally too, visiting other labs and collaborating with others (as Stacy and Hussein have already blogged about). I should probably introduce myself first. Hi, I’m Pamela Grothe, Kim’s newest PhD student, blogging from Southern California. I started at Georgia Tech last August and am just beginning to wrap up my second semester. A bit about myself, I’m a native Virginian, however, I’m a Coloradan at heart. I moved to Atlanta from Boulder after spending the last four years there, working as a research assistant in a NOAA lab and completing my master’s degree at CU. Everyone tells me I’m crazy for trading Boulder for Atlanta, but hey, it’s ONLY five years, right! Other than science, I love to run and race. I also love to bike and swim, hike and camp, scuba dive and kayak, and whatever else that involves the outdoors – I think that is par for course for anybody working in the earth sciences.

My Research

A ridge of fossil coral rubble  on Christmas Island
I fall on the coral side of the Cobb Lab (despite the photo of me in a caving helmet). For my research, I will be working on a new method of using hundreds of short (5-20yr-long) fossil coral segments (a.k.a. rubble) to reconstruct the El Nino-Southern Oscillation (ENSO) and tropical Pacific climate variability over the last 7,000 years in the central tropical Pacific. To date, paleo-ENSO variability has relied on exceedingly rare, decades-long fossil coral sequences, 16 of which are presented in Kim’s new Science paper spanning the last 7,000 years. However, smaller fossil coral rubble pieces are plentiful on Christmas Island (see photo at right, and which the gang graciously collected samples of last May). The plan is to use these numerous but shorter rubble pieces to produce a more statistically robust paleoclimate reconstruction – it’s all about the numbers! That’s the gist of the project, which I am only just beginning and super excited about!

Southern California

With any type of paleo-reconstruction, in order to put your record in context, you have to know how old your sample is! And that’s why I’m in California. I’m here to date the fossil coral that the group collected all across Christmas Island last May. My new approach of using hundreds of fossil coral rubble presents a unique challenge to me though. As you recall from Stacy’s dating lesson on U/Th dating, it is a quite intensive and time-consuming technique and thus very inefficient for quickly dating hundreds of sample at a time. So I’ve been in touch with collaborators Dr. John Southon and Dr. Guaciara do Santos at University of California Irvine’s Keck Accelerator Mass Spectrometry Lab, working with them on a method to quickly date lots of sample using high throughput radiocarbon dating (up to 60 per day)!

So in a nutshell, that’s who I am, what I’m working on and why I’m in California. Next up will be more details on my actual trip, which also includes a side trip to Chris Charles' lab Scripps Institution of Oceanography in La Jolla to sample fossil corals that Kim collected back in 1998!