Jennifer MacKinnon and the swirly things

Most of the big stuff in Earth system science arises from the small stuff. The Keeling curve is the balance between an unknowably large number of microorganisms and the cellular fixation of carbon. Clouds, covering more than half of the planet at any one time, are created at the sub-cm scale. And, increasingly, we are realizing that ocean circulation — once conceived as a sort of monstrous conveyor belt — is instead a motley crew of what Jennifer MacKinnon from the Scripps Institution calls “the swirly things”. Eddies, turbulent billows … “there’s just a ton of animals in the zoo”. Jen talks Mike through the close linkage between observations and theory: it’s hard to conceive of an Antarctic Circumpolar Current composed of a horde of eddies if you can only look over the side of one ship at a time. And the more we observe the ocean, the more interesting it becomes. It now looks, for example, that there may be super-weird interactions between internal waves and mesoscale eddies. More is coming, too, probably from Deep Argo. Yet beyond observations and theory — and as we also heard from Bill Boos — Jen’s kind of science can play a key role in advancing societally-relevant prediction systems. Plus, sabbatical in Palau*, wrestling, and Walter Munk is turning 100 — the party is on!


Music: Springish, All Eventualities and The Everlasting Itch For Things Remote by Gillicuddy. CC BY-NC 3.0.

*In the interview I said that Palau is in the Eastern Pacific. It is, of course, in the Western Pacific.

Josh Willis

Normally my show notes are carefully reasoned, sober discussions of the remarkable pathways forged by inspirational scientists, and their subsequent breakthroughs. Not this time. This time, I will begin with a headline about today’s Forecast victim guest, Josh Willis, that might be suitable for The Onion:


Idiot leftist scientist thrown out of school, concludes that warm water melts ice


Josh Willis

This is all true, from a certain point of view. Josh was called an idiot leftist scientist by Rush Limbaugh (a moniker enthusiastically adopted by Josh and, err, Josh’s wife), had to leave his PhD program in Physics, and is now leading the massive Oceans Melting Greenland program. But a more realistic telling is doubtless in order.

Josh grew up in Texas and completed a bachelor’s degree in Physics at the University of Houston. There, in the honors program, he met his future wife, a California native. The two soon relocated to SoCal, where Josh entered the PhD program in physics at the University of California San Diego and his wife attended medical school in Los Angeles.

Physics, however, was not to be Josh’s calling and he ultimately did not pass the departmental examinations. Although he came out with a master’s degree in physics, the experience was certainly a setback, and one that took Josh a year or two to get over.

Failure, as is so often the case, had an upside. Rather than inducing a downward spiral, the physics experience ultimately proved a huge relief for Josh, and one that led him to a vastly more fulfilling career studying oceanography at Scripps, where he worked with the great Dean Roemmich. There, Josh did some of the early work on coupling satellite altimetry with ocean observations to estimate ocean heat content.

The start of Josh’s PhD coincided almost exactly with one of the most important advances in oceanography, maybe ever: the Argo program. As Josh says

It was super exciting … it was also kind of scary … In retrospect it seems obvious, but at the time, it was almost crazy

The launch of the incredible Argo data stream created nearly new fields of inquiry, particularly into ocean heat content. But as is the case with any new data explosion, particularly when trying to bolt it onto older datasets, problems can emerge. Josh and his colleagues published a paper entitled “Recent cooling of the upper ocean“, but soon found out that the cooling was due to problems in both the earlier XBT data and software problems in a group of North Atlantic Argo floats. A correction soon followed. I completely view this as a positive, rather than negative, example of how climate science actually functions: scientists follow the data, and revise their conclusions based on new information.

Unfortunately, Josh figured out the error upon walking out the door for a Valentine’s day dinner with his wife. Dinner was a disaster, and

As retribution, my wife had business cards made that have my job title as idiot leftist scientist

Josh’s fake business card, kindly made by Josh’s wife after he botched a Valentine’s day dinner.

Now Josh is pursuing one of the main topics in sea level research: the interactions between Greenland’s marine-terminating glaciers and the surrounding ocean. Prior work had revealed some of these interactions in particular fjords, but Josh and his colleagues are now conducting systematic radar surveys of all of Greenland’s outlet glaciers, combined with sensors parachuted into the fjords. The project — Oceans Melting Greenland — is in the data collection phase, and is part of a recent special issue in Oceanography. Once complete, we should have a much better idea of how and where ice-ocean interactions are strongest, and what the implications will be for sea level rise.

Josh has a wicked sense of humor, even in the face of potential impending disaster for federally-funded climate science. Just check out Dick Dangerfield on the video section of the OMG Facebook page. I like episode 1 in particular.


Music: As Colorful As Ever, by Broke For Free. CC BY-NC 3.0.

Amelia Shevenell, big ideas and big risks

Amelia Shevenell from the University of South Florida specializes in big ideas about paleoceanography and the Antarctic Ice Sheet. She’s also keen to push the methodological envelope, which can be risky if things go pear shaped. For Amelia, though, the work resulted in papers in Science (Mg/Ca) and Nature (TEX86). Continue reading →

Tina van de Flierdt explains paleoceanography proxies

Tina van de Flierdt from the Department of Earth Science and Engineering at Imperial College London is an international leader in the use of geochemical proxies – particularly neodymium (Nd) – for reconstructing past ocean circulation, water masses and weathering. But her childhood and early interests pointed in a different direction. Continue reading →

Lixin Wu and the rising tide of Chinese oceanography

I met Lixin Wu when I was at the Ocean University of China in Qingdao for a writing workshop (now called Nature Masterclasses). Several things impressed me about Lixin right away. First, he’s a lot of fun to be around and equally at ease in formal situations and banquets. Then, he’s clearly an inspiration to his staff and colleagues. Finally, he has big visions for his own science, the OUC, and Chinese marine science in general.

Continue reading →

Into the deep ocean with Lorraine Lisiecki

Lorraine Lisiecki is in the business of understanding past variations in ocean circulation. In particular, she uses mathematical approaches to interpret observed variations in δ18O and δ13C on times scales of thousands to millions of years.

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Amy Clement questions the core ideas of climate dynamics

Essentially from the start of her career, Amy Clement has been interested in the big ideas in atmospheric dynamics. But she’s also continually raised questions and proposed her own sometimes controversial ideas.

Amy Clement
Credit: UM Rosenstiel School of Marine and Atmospheric Science

El Niño is fundamentally linked to atmosphere-ocean interactions? Maybe not. The Atlantic Meridional Overturning Circulation drives the Atlantic Multidecadal Oscillation? Again, maybe not. Continue reading →