The arc of TEX86 with Jessica Tierney

In this episode of Forecast, Jess tells Mike about the origins of the TEX86 temperature proxy — an index of membrane lipids produced by mesophilic archaea. The origins in the 1980s in extreme ocean environment; discovery of membrane production in a huge range of environments; brute force discovery of the index; the inevitable struggles to understand what it actually represents; an unusually active and sometimes dismissive debate about its usefulness. All proxies have issues, but Jess and her colleagues are converging on the what/when/where for TEX86’s application. For Jess, work on TEX86 (and other methods!) is leading to an improved understanding of the atmospheric dynamics, surface processes, and feedbacks governing past climate variability, particularly in the tropics.

Jess Tierney

Connecting Kevin Anchukaitis

Kevin Anchukaitis from the University of Arizona is probably best known for his work on dendroclimatology, but this is changing quickly. Now, his broader interests in the connections among history, political science, archaeology, statistics, climate modeling, and forward modeling of proxies are increasingly mirrored within the broader field of late Holocene paleoclimate research. Now, it’s possible to bring together this astonishingly wide range of evidence to disentangle, for example, the influence of volcanic eruptions on climate and society. It ends up sounding like a golden age for climate science, if not for the extinct Monteverde golden toad, whose extinction Kevin showed to be due to a fungal disease coupled with natural climate variability. As always, with good science, you have to go where the evidence takes you.

Trace metals and thrash metal with Kaustubh Thirumalai

People find science for all kinds of reasons. Some are born to it, but usually not. Most people find science by bumping into it at a bar, getting help from it while fixing a flat tire, seeing it alight on a leaf, iridescent, or watching it pass by on a subway car going the other way.

Kau aboard the JOIDES Resolution as part of Expedition 353, sailing in the Bay of Bengal in 2015. Photo by Sungham Kim from the Korea Polar research Institute.

For Kaustubh Thirumalai (Kau), the stage was set with burnout on chemical engineering in India coupled with a side job reviewing comics and black metal for a friend’s website. Then, almost randomly searching for an interesting internship, he hooked up with Prosenjit Ghosh, for whom he worked as a local fixer, helping to procure parts for the construction of a mass spec. After that, it was geosciences, full-on: a move to the US, interests in the techniques and concepts of paleoclimate, and an ever-expanding network of collaborators. But still comics and metal! Just now with a splash of trace metals — little bundles of strontium and company, waiting to be discovered.


Intro music is from the album Terminal Redux by Vektor, ranked by Kau as the #1 metal album of 2016. Extro music is Quartz, by Kau himself. All music used by permission — thanks Dave and Kau! Photos are by Kau, used by permission.

The Atlantic’s Rob Meyer on climate journalism

Sometimes papers in Nature are incomprehensible to anyone other than a hard-core specialist. Yes, we use press releases, News & Views, and other reporting to make the leap to our broader readership. But for bringing science to the general public, no amount of Carl Sagans, Neil deGrasse Tysons, or Bill Nyes is going to get the job done. You need journalists. Journalists like Rob Meyer from The Atlantic, who are producing an astonishing amount of great content on topics like the Paris Agreement, fracking regulations, and Antarctica. Rob talks me through his path from music major to twitter procrastinator to Atlantic writer. I flip the usual Nature-related questions around to Rob: how do you select stories, frame them for your audience, and discuss the policy implication? And what is the rationale for the New York Times hiring Bret Stephens? Definitely a story there.

Rob Meyer from The Atlantic

Music: Clips for the intro and extro are the songs 1969 and One Ticket Two Bills by Ending Satellites CC BY-NC-SA 3.0.

Extremes are the new normal, with Sarah Perkins-Kirkpatrick

The causes of heat waves are kind of like the controls on a car. We know that pressure systems, land-atmosphere interactions, and modes of variability like ENSO act to control extremes, just as we know that the steering wheel, moderated by the brake and gas pedals, controls the direction and velocity of the car. But imagine driving a car blindfolded. Yes, you know what the controls do, but the chances of hitting something hard are pretty high if you keep the gas pedal down, careening across even the most familiar of roads. For extremes, the moment-to-moment, season-to-season occurrence of extremes will remain challenging to predict, like the exact moment at which you’ll veer out of your lane, but the coming impact of blindly increasing emissions is more certain. Sarah Perkins-Kirkpatrick from the University of New South Wales endured the horrendous heat of Australia’s 2017 summer – pregnant, in a badly insulated house with wobbly air conditioning – and is studying heat waves and how they will change in a persistently warming climate. As Sarah tells Mike, the news is almost uniformly not good. Unless the foot comes off the gas pedal, the car is going to hit the wall: rare events in today’s climate are likely to become seasonally persistent; different emission pathways might delay but won’t alter the ultimate arrival of catastrophic heat. Of course, society could adapt, and Australians could end up living the bulk of their lives in air conditioned spaces, at the cost of further emission increases, radical changes to lifestyle, and eye-popping expense. Is this the world we want? Let’s hope not, but the mitigation equivalent of self-driving cars is not going to magically appear. It’s just us.

Music: Balkan Qoulou by Watcha Clan CC BY-NC-SA 3.0 US; Backed Vibes Clean by Kevin MacLeod CC BY 3.0

Climate economics with Sol Hsiang

The field of environmental economics in general — and climate economics in particular — is exploding. And my guest on episode 44 of Forecast, Solomon Hsiang from UC Berkeley, is helping to crack open some of the recalcitrant oyster shells of the field. How does climate influence conflict, migration and economic productivity? We talk through some of the big challenges in addressing these topics: the frequent impossibility of running experiments and the accompanying use of quasi-experiments; the growing use of — at last! — data; how incredibly hard it is to disentangle the influence of single factors — like climate — in a complicated human system. In many ways economics is decades behind physical sciences. As Sol explains, we’ve now for the most part forgotten about the initial debates regarding fluid dynamics, but economics is still very much at the phase of figuring out elementary processes. Sometimes this means that the major findings reside in statistical approaches, without clear mechanistic understanding. But Sol and his colleagues are working towards linking microscale human decisions to aggregate societal processes, and it is this sort of understanding that will, and indeed already is, proving important in a policy context.

Credit: Brittany Murphy

Music:  Le train pour Paspébiac, Quand la bière est tirée and Matelot by QuimorucruCC BY-NC-ND 4.0.

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.

Climate policy with Gretchen Goldman

Forecast is mostly about climate science — the people who do it, and why they’re stoked about their work. But science is inevitably conducted within a political context, and Mike is a neanderthal when it comes to politics. Gretchen Goldman from the Union of Concerned Scientists, on the other hand, knows a lot about science policy. Gretchen initially planned to avoid the often-unpleasant dynamics surrounding climate science, and went into air pollution research. Eventually the draw of engaging in even bigger issues proved too much to resist, and Gretchen is now the research director for the Center for Science and Democracy at the UCS. Gretchen leaves Mike feeling surprisingly optimistic. In spite of the dark times facing US climate science, and as Gretchen discusses in a Science Policy Forum, there are still clear ways for scientists to engage with the broader public and to promote the use of science in the democratic and policy process. For those interested in getting more involved, the UCS provides excellent resources for networking and dealing with personal attacks.

Disclosure: As Gretchen discusses in the interview, her husband works at NOAA, an agency whose budget faces major cuts. He is also the consulting meteorologist for

Music: Hashashin by Metastaz, CC BY-NC 4.0.; A1 Rogue by Podington Bear, CC BY-NC 3.0.

Jana Sillmann and climate extremes

Jana Sillmann has carved out a career working on understanding and predicting climate extremes — heat waves, heavy rainfall, atmospheric rivers. What combination of factors controls the occurrence of extremes, particularly in a changing climate? Jana and Mike hash through the underlying science — including the agonizingly slow pace of model development — and how society is affected by and responds to extremes. Jana’s background and pathway to her current position are equally fascinating: an idyllic childhood in communist East Germany, with mom teaching construction; exchange student in rural North Dakota, hosted by an accordion virtuoso; grad school in the US; realizing that a career with computers and coffee was preferable to field work; chance exposure to an inspirational talk by Mojib Latif; a PhD from the Max Planck in Hamburg; four years in Canada with people like Francis Zwiers; leaving Canada in response to the anti-science politics of the time (sound familiar?); finally, moving to what sounds like a fabulous position at CICERO in Norway, where, remarkably, society actually seems to fully support women in science. And the ideal science environment? A sprinkle of Norwegian funding for individual academics, a bit of German support for postdocs and grad students, and a splash of Canadian IT investment.

Jana Sillmann. Credit: CICERO

Music from the album Encounters by Metastaz CC-BY-NC 4.0. Includes the tracks HashashinVampire, and Girl and Assassin.

Monsoons with Bill Boos

Bill Boos and I have something in common. Neither of us is much of a long-term planner, but we both like to take advantage of opportunities as they arise. For me, this approach led to a switch from academia to editing. For Bill, it led to an in-process move from Yale to UC Berkeley.

Bill’s career had plenty of twists and turns along the way. Namely, we almost lost him to the dark side … a career in financial consulting at Anderson (now Accenture). Happily, that path didn’t prove sufficiently interesting, and Bill landed in a terminal one-year MS program at MIT, where he started his work with Kerry Emanuel. Except it wasn’t so terminal.

Post-graduation, Bill checked out the professional job market, but quickly found that:

The best job that I’ve interviewed for is not as interesting as staying in graduate school

Things started to click with Kerry, and Bill pursued work on fairly theoretical ocean and atmospheric dynamics. But soon after graduation he published a landmark paper suggesting that a strong Indian monsoon can be generated solely by the presence of the Himalayas: no Tibetan Plateau required. I found the paper fascinating when I handled it at Nature, and it certainly stirred things up in the monsoon community.

As I’ve mentioned on the show in the past, monsoons are endlessly vexing: tantalizing but ephemeral teleconnections; busted predictions; monstrous interannual variability; conceptually simple but terribly complex in the details. One approach to disentangling the mess might be, as Bill puts it, to start off with a clear null-hypothesis:

Can we disprove the hypothesis that this year-to-year variability is just random and we’ll never be able to predict it?

Answering the question would inevitably take a renewed focus on observations, a deep dive into reconstructing past variability, and improved dynamical understanding.

One area of low-hanging fruit — or at least fruit that could be reached by a long extension pole, perhaps while teetering at the top of a rickety three-meter wooden ladder, the base of which has long been under assault by termites — is monsoon depressions. These systems, a topic of much research in the 1970s-1980s, don’t look that horrendous in comparison to typhoons, but end up generating some of the most destructive storms. Why? Bill would like to know. Me too.