Climatide

Earlier this week, NewsWeek ran a cover story with the headline “Are you ready for more?” What followed was an in-depth look at climate change impacts and the need for adaptation measures, by science editor Sharon Begley. Sharon argues that the extreme weather of the past year – and the toll it has taken in terms of both dollars and human lives – makes it clear that we aren’t ready for what’s to come.

I certainly won’t quibble with the fact that climate change has begun to – and will increasingly – make life rough for a lot of people, or that we need to put more effort into planning for and adapting to the inevitable impacts of climate change. And I’ve enjoyed Sharon’s work in the past. But in this case, I wondered if the language might feel melodramatic to the average reader. Take this, for example:

It threatens to be a trail of human misery that will make the exodus after Hurricane Katrina look like a weekend getaway.

I questioned a few factual statements, in particular. And I wasn’t alone. Dot Earth blogger Andy Revkin posted a brief retort (nigh on dismissal) on his tumblr account, and several of the comments on the Newsweek website were skeptical.

So I decided to do some fact-checking. I used the Climate Science Rapid Response service to get leading climate scientists’ perspectives. I also drew on direct quotes from scientists found in past media reports. And I sent my critiques to Sharon so she could respond. Here’s the blow-by-blow:

1. Extreme weather

What Sharon wrote:

Even those who deny the existence of global climate change are having trouble dismissing the evidence of the last year. In the U.S. alone, nearly 1,000 tornadoes have ripped across the heartland, killing more than 500 people and inflicting $9 billion in damage. The Midwest suffered the wettest April in 116 years, forcing the Mississippi to flood thousands of square miles, even as drought-plagued Texas suffered the driest month in a century. Worldwide, the litany of weather’s extremes has reached biblical proportions. The 2010 heat wave in Russia killed an estimated 15,000 people. Floods in Australia and Pakistan killed 2,000 and left large swaths of each country under water. A months-long drought in China has devastated millions of acres of farmland.

What the scientists say:

One thing is certain: temperatures are rising, and warmer air holds more energy and more moisture – the ingredients for stronger storms. Climate scientists are virtually unanimous that global warming will lead to more extreme weather.

But the question of whether climate change is responsible for the extreme weather of the past year has been a recurring topic virtually anywhere that weather or climate change is mentioned (and that’s a lot of places). Unfortunately, there’s no satisfying answer. There’s not even one single answer. Ask eight different scientists and you’ll get eight different answers; the editorial team at Yale E360 did exactly that, and the result is some highly recommended reading.

I think Katherine Hayhoe, a climate scientist at Texas Tech University, has done a nice job summing up both the human tendency to look for connections and the difficulties of proving those connections scientifically:

Whenever we see a season like we’re having right now, it’s a natural part of being human to say, is there a pattern to it?

And so, of course, that’s what we’re asking right now: Is there a pattern to all of the weird weather that we have been seeing this spring? Unfortunately, at least for those of us who want a pattern immediately, we can’t tie any one event or even one season to climate change.

Climate is the average statistics of weather over at least 30 years. But what we can do is, we can add this season to the books, and we can start looking at whether we see any trends in heavy rainfall events, in droughts and in tornadoes.

When we do that, we do see trends in some things. We see trends in heat wave frequency and severity in many places around the world. We also see increases in heavy rainfall events across the entire U.S., especially in the Midwest and the Northeast.

But when we look at the tornado record, we don’t see any conclusive trends in tornado numbers or severity yet.

Sharon’s response:

That was based on reporting I did for a column last year describing research that’s making progress attributing particular weather events to overall climate change rather than cyclical, non-global-warming events or simply random fluctuations. As you note, the 2010 Russian heat wave has not yet been so attributed (but as you also note, the case is not closed); ditto–to even greater certainty–the recent tornadoes. I included examples of this and other extremes simply to make the point that in a system with more heat energy, we’re going to see more of them. I think it’s interesting that the decades-long mantra–’no single weather event can be blamed of global warming’–might, thanks to the new statistical techniques pioneered at the Met Office, not be true much longer.

2. 12,000 years of stability

What Sharon wrote:

From these and other extreme-weather events, one lesson is sinking in with terrifying certainty. The stable climate of the last 12,000 years is gone. Which means you haven’t seen anything yet. And we are not prepared.

What scientists say:
I got feedback from four leading climate scientists on this one. Again, no two answers were identical. Henry Pollack, a professor at the University of Michigan and author of A World Without Ice made the point that stability is a matter of perspective.

The standard answer to that question is ‘yes’, but the important contextual question is, stable compared to what? Over the past 10-12 thousand years the fluctuations in Earth’s average surface temperature have generally been in the range of 1-2 degrees Celsius (or smaller). However, for several tens of thousands of years prior, the fluctuations were an order of magnitude larger, 10-20 degrees Celsius

But Ray Bradley from University of Massachusetts, Amherst, pointed out that the climate of the past 10,000 years was not nearly as stable in the tropics as it was in higher latitudes. And Woods Hole Oceanographic Institution’s Lloyd Keigwin emphasized the difference between the rate of change (which he said has been similar for hundreds of thousands years) and the extremes that are reached.

But Robert Wilson, from University of St. Andrews, really got at the heart of the matter:

If we acknowledge that the climate of the last 400,000 years is a result of a natural interchange of factors, … the new factor that we need to worry about is Man’s influence on the atmosphere. If we look at CO2 emission alone for the last 400,000 years, the recent increase in CO2 is unprecedented. It is for this reason why the Newsweek article says that “the stable climate of the last 12,000 years is gone”. We are moving into unexplored territory and temperatures WILL increase. Of course there is uncertainty as to whether this increase is going to be 1 degree, 2 degrees or more, but even a further 1 degree Celsius global change over the next 20-50 years will put the global climate system into a state that the planet has not experienced at least for the last 400,000 years.

Sharon’s response (my emphasis):

Stability is a subjective term, so I used (in my own mind; no room to spell it out in the story) maximum temp variations: the 1-2 degrees of swing over the last 12,000 years is less than over the preceding millennia, and seems to be/may be a regime we are leaving behind. Although global mean temps are up only 1 degree or so, the arctic and even some lower-latitude regions have experienced far more.

3. Longer runways

What Sharon wrote:

Because warmer air provides less lift, airport runways the world over will have to be lengthened in order for planes to take off.

What scientists say:

Here, again, scientists’ responses varied. Some had personal experiences with departures delayed because it was too hot for the plane to take off in the space available. All agreed that, while the theory is sound, the real-world relevance is suspect. This may be an issue in some places, or centuries from now if carbon dioxide emissions go unchecked. But it’s unlikely to be a widespread problem in the near future.

Sharon’s response:

I think the runway example is fascinating, and included it only because it was so different from the other climate-change adaptations we may have to make. ‘Widespread’ issue? Maybe not, but of course I didn’t say so. To my knowledge, no aviation authorities have analyzed how much of a safety margin their airports have – obviously, planes take off from JFK and Logan even when it’s 100 degrees. I was sensitized to this issue when I was stuck in Aspen, after doing a panel at an Aspen Institute health forum a few years ago, because airport authorities wouldn’t let us take off: the heat that day, they said, meant the plane was at risk of not clearing the nearby mountains. It left an impression.

The Verdict

After all that, here’s what I’m left thinking: Sharon and I, and the many scientists whose work we attempt to portray for the public, are on the same page (or at least the same chapter) when it comes to the impacts of climate change. I found no egregious errors in her article. And, as I told Susan in our email exchange, the call for greater attention to adaptation measures is a prudent one.

My discomfort was entirely a matter of nuance. Climate change is complicated; trying to hide or deny that fact does no one any favors. Indeed, exaggeration – even the appearance of exaggeration by omission of details about the complexities and limitations of the science – can backfire, causing readers to discount the whole story. That was apparent in some of the responses to Sharon’s article.

I’m not saying every minute detail needs to be trotted out; I certainly left out more than a few from the email exchanges that went into this piece. But I wanted to point out that this is difficult, that these questions are nuanced, and the complexities of the science might not respect our space limitations. If we state our perceptions too boldly, we run the risk of crying wolf. But if we don’t talk about climate science at all, we risk an even greater peril.