Category Archives: El Niño

Urgency and Uncertainty in Rolling Stone

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Eric Holthaus has a recent piece in Rolling Stone enitled “The Point of No Return: Climate Change Nightmares Are Already Here.” The subtitle is “The worst predicted impacts of climate change are starting to happen — and much faster than climate scientists expected.”

It’s a good article. But it highlights the difficulty of talking about current extreme weather events and their relation to human-induced climate change. On the one hand, the essential message of the piece is to communicate urgency on climate and need for action. This is right and appropriate. And sentence by sentence, the individual statements about specific weather and climate phenomena are accurate (at least those where I have adequate expertise to make an evaluation).

On the other hand, the piece implicitly attributes a lot of individual weather and climate events – all of those it mentions, really, which is a long list – to human induced climate change. Some of those attributions are justified, but others aren’t.

In the cases where the attribution isn’t justified, Holthaus doesn’t explicitly make it, not line-by-line in the sentences talking about those events. I couldn’t find anything outright wrong at that level. The piece was, clearly, researched and written quite carefully and with deep respect for the science. But the attribution is there implicitly, through the piece’s headline, its subtitle, and its overall framing.

I’ve added some annotations at the site Climate Feedback (my annotations and others’ on this piece are not visible yet, as far as I can tell; soon, I think), a new site designed for scientists to evaluate the science content in popular articles on climate. Two of my comments are about Holthaus’ discussion of the ongoing El Niño and positive phase of the Pacific Decadal Oscillation. These two are enough to make the point I’m interested in here.

These two climate phenomena, manifest by slow changes in the sea surface temperature in various parts of the Pacific ocean are indeed having major impacts, as described well in the article. But most climate scientists consider these phenomena to be essentially natural. We can’t be certain that the current instances of El Niño and the Pacific Decadal Oscillation aren’t in any way connected to human induced climate change, but there is no convincing evidence of such a connection, to my knowledge. Holthaus doesn’t say there is one, but to my eye it’s clearly implied. The title and subtitle, as well as the overall framing of the piece, say that it’s a list of impacts of “climate change” – which presumably most will understand to mean “human induced climate change”.

I’m being critical on this issue because it’s one I struggle with myself, and because Holthaus is a thoughtful, serious and committed writer on climate, one who actively seeks criticism from scientists (I understand that he asked Climate Feedback to evaluate his piece). And because while I read the piece as making some implied claims that are outside what science can justify, I agree completely with its bottom line, and appreciate the force with which it comes across.

Human-induced climate change is real, is a grave threat to human society, and is already having significant impacts now. Some of the events Holthaus describes almost certainly do have some imprint of human influence: heat waves and ocean acidification, for example. And natural and human influences can’t be completely untangled. While the heat, drought and wildfire in the west now are likely caused in large part by natural variations in the Pacific sea surface temperature (El Nino and Pacific Decadal Oscillation), greenhouse gas warming adds extra heat, making the impacts worse.

And regardless of the causes of individual extreme weather and climate events now, the disasters they cause still tell us something about our vulnerabilities, and that is relevant to the longer-term climate change question. The human influence will grow larger in the future, as warming proceeds. It will eventually make some kinds of extreme events significantly, detectably more frequent or more intense, even if we can’t clearly detect that influence in individual events of that type happening now. (Tropical cyclones are a good example of this.) The current events can rightly be seen as harbingers, if nothing else.

Holthaus writes quite a bit about the recent paper by James Hansen and colleagues, which warns that sea level rise may occur much sooner and more severely than most of us had thought. This paper is controversial, and not yet even through peer review. But in my view it deserves the coverage it gets, here and elsewhere – its predictions may or may not be right, but it seems pretty clear that we can’t rule them out. Contrary to denialist lines of argument, the uncertainties in climate projections should make us more worried, not less.

What if Holthaus had made a more concerted effort to avoid any implication of human influence on events to which it wasn’t justified? In a piece with the title and subtitle that this one has, the simplest way to do that would have been not to write about those events at all. That would have meant leaving out some of the most serious and visible disasters going on right now in the US, where the main readership for this piece presumably is. Alternatively, the piece could have had a different title and subtitle (my guess is that these were written by an editor rather than by Holthaus himself), one that communicated that the piece was about events of both natural and human origins. Either way, would the sense of urgency have been diluted?

Professional scientists are sometimes criticized for under-communicating the urgency and reality of climate change, especialy when we talk about current extreme events. This criticism is often fair in my view. We talk so much about the uncertainties that we leave nonscientist audiences with the feeling that we don’t know anything. We do this, I think, because we are used to talking to each other. Being clear about uncertainties is an inherent part of scientific practice. Also, our colleagues already share our knowledge and understanding of the big picture on climate change – the consensus is real – so we don’t feel a need to restate that. We fail to recognize that that underlying knowledge is not shared outside our professional circles, and that it’s often appropriate to emphasize what we do know more than what we don’t.

Journalists, on the other hand, are often criticized by scientists (and others) for overstating the connection of extreme events to climate change by glossing over uncertainties – as I have done here, in my first few paragraphs above. This is also often fair, and as with scientists, similarly traceable to the daily realities of their jobs. Journalists are under great pressure to make it current, make it exciting, keep it simple. It’s easy to see how that leads to a little exaggeration and overstatement, whether by implication or outright.

If there’s a perfect solution I don’t know it. I’m glad that writers like Holthaus (and many other good ones) are grappling with the science and doing their best to keep it accurate while still getting the essential message on climate into the popular press. I don’t love everything about this Rolling Stone piece but I think we need more like it anyway.

Full disclosure: Eric Holthaus is an alumnus of Columbia University, where I teach, though I didn’t teach him when he was here and haven’t met him in person to my knowledge. He has interviewed me a couple of times for other pieces he has written, though not for this one in Rolling Stone. He wrote a very kind review of my book when it came out last fall.

The extreme state of the Pacific climate

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I have a post up at the Columbia Earth Institute State of the Planet via the Initiative for Extreme Weather and Climate, on the current El Nino event, recent Madden-Julian Oscillation, typhoons and hurricanes, and everything else going on in the tropical Pacific now, as well as its impacts on the US, and the ramifications (including some pretty speculative ones) for the global climate.

El Niño, Tornadoes, and Hail

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I am a co-author, with lead author John Allen and second author Mike Tippett on a paper that just came out today in Nature Geoscience. This paper quantifies, better than had been done previously, the relationship between El Niño or La Niña events and severe weather – tornadoes and hail – over the United States. The big conclusion is that knowledge of the state of an El Niño or La Niña during winter can be used, in principle, to forecast changes in the probability of severe weather the following spring, several months ahead. The relationship is such that tornadoes and hail are suppressed in an El Niño year (enhanced in La Niña). This seems to be playing out so far this year, as March has been dead tornado-wise and we are indeed in an El Niño.

This paper is getting some media attention. So for more detail, please look at Climate Central, Bloomberg, Phys.org, The Carbon Brief, Science Magazine, or LiveScience.

Climate Services: Two conferences on two continents

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I spent this past week in Darmstadt, Germany, for the Climate Symposium. This was a conference organized by EUMETSAT (one of the European space agencies) and the World Climate Research Program.

The conference had a couple of goals. Perhaps most prominent was to “ascertain critical objectives to be achieved with satellite-based climate information, and identify gaps in the current space-based component of the climate observing system” – in other words, help EUMETSAT decide what new satellite instruments to build and launch in the coming years. The idea here was to present the current state and future needs of climate science in order to determine how new satellite observations could help. The climate science was presented through the lens of WCRP’s new Grand Challenges. (I am involved directly in one of these, on Clouds, Circulation and Climate Sensitivity, and interacting with the leaders of another, on Understanding and Predicting Weather and Climate Extremes.)

Climate science justifies its funding largely on the basis of its benefit (real or potential) to society, and that justification was particularly explicit at this conference. A lot of the program was devoted to “Climate Services”. This term refers to entities and people whose jobs lie in between the physical science of climate and “users” of climate information, also known as “stakeholders”. Climate Services involves translating the information that climate science can provide into terms that will be most useful for specific human purposes. (In the US, NOAA tried a few years ago – at the instruction of President Obama – to create a National Climate Service, with a status analogous to the National Weather Service. Congress, much of which hates even the word “climate”, killed it.) In practice, Climate Services is about taking the time to learn what specific users’ needs are, teaching those users what climate information current science can and can’t provide, and packaging the information to make it easier for them to digest.

Most of what I know about Climate Services comes from the International Research Institute for Climate and Society (IRI) at Columbia, which has been providing climate services since well before I (or most other people) ever heard the term. I was initially hired at Columbia through the IRI, which came into being a couple of years before I arrived here in January 2000. The IRI, in turn, exists because of the work of Mark Cane.

In the 1980s, Mark and his then student Steve Zebiak (later to become a founding member, and then director of IRI) developed the first numerical model that was capable of predicting the El Niño/Southern Oscillation (ENSO) phenomenon. They demonstrated this by making a successful prediction of the 1986/87 event.

While ENSO occurs in the equatorial Pacific, it has influences on climate and weather across much of the earth. An El Niño, for example, typically causes drought in Australia, Indonesia, southern Africa, and northeast Brazil, wet weather in southern California and unusually clear weather in the Pacific Northwest, and fewer hurricanes in the Atlantic, among other changes. Cane and Zebiak realized that the forecast capability they had developed had the potential to make a positive difference to the lives of a substantial fraction of the planet’s population. By knowing something about how the upcoming season or two would be likely to differ from the usual, people and governments could plan ahead across many sectors of activity: agriculture, water, health.

The IRI was created to realize that potential, and has been working with countries around the world for over 15 years to that end. While the notion of Climate Services now is as much about long-term anthropogenic climate change as it is about interannual variability (a la ENSO), ENSO and the IRI were at the start of it as much as anything, and are still a critically important component.

Tomorrow – Monday October 20 – we will start The Tropics Rule, a Symposium Honoring Mark Cane’s Contribution to Climate Science. This will be a two-day event on the occasion of Mark’s 70th birthday, featuring a long list of distinguished scientists presenting new research and historical reflections on Mark’s long career of truly amazing scientific achievements. It will take place in Monell Auditorium, the physical home of the IRI, on the Lamont Campus.

So in summary, I got on a plane to fly to Germany for a conference where I heard about the present and future of Climate Services. Then I got back on a plane to fly home to attend another conference at my own institution, in honor of the scientist who, it is not a great exaggeration to say, invented the idea.