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Are crocuses in January a sign of the apocalypse?
But wait! San Francisco is experiencing record cold, prompting a state of emergency. Blizzards and avalanches are hitting the middle of the country. And no less an authority than the National Weather Service has declared that the recent warm temperatures have nothing to do with global warming. Blame El Niño instead. So which is it? Is the warm weather a direct result of global warming, of El Niño, or of some other unknown phenomenon? The short answer is: who knows? A longer answer is that it’s important not to confuse weather and climate. Climate refers to a broad set of conditions that characterize the atmosphere over decently long periods of time. Weather is a snapshot of those conditions at any one instant. Although the two are clearly related, the relationship is indirect and statistical. It’s not possible even in principle to trace back a single weather event to any distinct cause. An even longer answer can be found on the ever-helpful and clear-eyed RealClimate, which digs into the recent weather patterns with gusto and finds all of the media-hyped explanations wanting. On the one hand, the Weather Service overstates its case when it ascribes all of the recent temperature spike to El Niño. For one thing, last winter was also anomalously warm, and at the time there was no El Niño. (In fact, we experienced its opposite, La Niña.) Also, the current temperature spike is about five times the effect of a typical El Niño. Taken together, these issues do strongly suggest that forces beyond just El Niño are at play. Further, the patterns of warm weather fit very well with those predicted by models of manmade climate change. So do we have our smoking gun? Not really. For one thing, the weather has been way too warm lately to be directly attributable to global warming. Recall that most climate change models predict an average warming of a few degrees over the course of the next century. A spike of 20 degrees over the course of a single week isn’t climate change. It’s a freak event. Which is basically what all weather is: a momentary circumstance reflecting a chaotic and indeterminate set of atmospheric conditions. The most that can really be said is that both El Niño and manmade global warming make the type of warm weather we’re presently seeing more statistically likely than it otherwise would be. Beyond the general wonkery, there is an important point here. It’s important not to get overly caught up in individual weather events, because the temperature pendulum is going to swing around quite a bit even as average temperatures gradually increase due to global warming. If overly much is made of every warm spell, skeptics are going to play the same game in reverse, turning every cold snap into another argument for inaction. Another important, but easily overlooked point is that climate change is about much more than just warming. As a resident of New York, I can personally attest to the fact that the current warm weather happens to be extraordinarily pleasant. But climate change — which we can take as a shorthand for species extinctions, extreme weather events such as hurricanes, drought, flooding, food supply disruptions, population dislocations, and a whole host of other effects — will not be pleasant. As always, it’s important to keep the big picture in mind. Comments10 comment(s) on this post. Leave your own!
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The cherry blossoms are blooming in Brooklyn. Golfers are hitting the links in Chicago. Ski resorts and ice fishing competitions suffer, while wineries and ice cream makers celebrate. 2006 was the hottest year on record. Even the staunchest global warming denialist must admit that the end times are nigh.
Thanks for this informative and balanced discussion. I was expected to hear you say that somehow we KNOW global warming is ABSOLUTELY the cause of this season's unusual warmth. I think people who aren't weather or climate professionals forget that just like there are daily cycles (warmer in the day, colder at night), and seasonal cycles there are also those with a much longer time constant, perhaps hundreds of years. Even that timeframe is a flash compared to the history of our planet and the solar system it lives in. Of course we still do need to reduce our emmissions because of the unprecedented industrialization of the last couple centuries. Thanks for being reasonable about it.
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Excellent commentary. This weather vs. climate distinction is one of the things that makes dealing with the public's perception on climate change so challenging, and it compounds the political risk of overselling the likelihood of the most extreme potential outcomes. Those of us who deal with this issue need to be prepared for the volatility of perception that weather events will naturally produce, as the global climate warms in fits and starts. After all, we are going to be coping with this for the rest of our lives.
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I too heard a report on NBC news about all this weird weather. Dennis Feltgen from NOAA in Washington, DC, just told the public last Friday on NBC news that the current weird weather over the last year is not the effect of global warming but the effect of El Nino. No explanation was given to support this viewpoint, just a simple, "No, it's not global warming it's El Nino, El Nino." Additionally, the report only looked at the weather in the US, and failed to include all the recent natural disasters and weird weather all around the world. With reports like this, no wonder Americans are still asking whether global warming is real or not. How can a venerable meterologist like Dennis Feltgen say this?
I wrote to NBC new, but I wasn't the only one who had a problem with this news report. NBC news addressed the public's concern regarding this show. However, the report still does not look at the global picture, the weird weather and natural disasters all over the world. When I went to the link a second time, both the old story and new story were no longer available. www.msnbc.msn.com/id/165310...yContinued (No longer available)
Now NBC is changing it's tune. Now they state that it is greenhouse gases along with El Nino.
www.msnbc.msn.com/id/16542693/
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Good job in this newsletter, Adam. Maybe some synergy happening between El Nino/La Nina & Global Warming? We can predict & extrapolate, but time alone will tell. We simply don't have the data for exact computations & we never will. Two relevant points--everything is connected to everything else and experience is the best teacher. If the world experiences more anomalous weather over the next several years, those of us who are concerned abour climate change won't have to yell loudly that the sky is falling.
For those who have seen the relevant TV ad, I for one am aware that a train is bearing down on myself & the child(ern) standing behind me. Let's work to get us all off this railroad track in a rational manner, lest we trip in panic, breaking a leg & slowing our move to safety to a painful crawl.
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I think everyone should watch the Inconvenient Truth, it explains everything. Global warming is causing all the crazy weather. The movie explains why some people get floods and neighboring areas get droughts.
And it will just get worse. More unpredictable and more sever weather will plague this.
The scientific data in the movie goes back and documents the carbon highs and lows through past ice ages, etc. and one thing is very clear. The carbon in the atmosphere now is insanely higher than it has ever been before.
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freak weather is almost an inconveniently truthful friend who will help accelerate growing public perception.
it used to be a "green" thing, now it is becoming more and more mainstream.
just in passing, they are tapping maple trees sooner and sooner. here in new england, this harbinger of spring, along with the arrival of migratory birds, whether caused by el nino, global warming or just regular normal fluctuations is causing people to take notice.
maybe they will do something.
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Adam,
I'm disappointed. You typically write so well. Where is the mistake in usage?
"no less an authority then the National Weather Service"
If you're looking for a proofreader, let me know.
-Adam
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I guess I do need a proofreader...and it looks like I've got one! Thanks for catching the error. I've updated the post.
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Educate -- good for you for writing to NBC. I think people underestimate how important simple actions like this are. And it seems to have worked, based on your comment.
KK -- I've seen and enjoyed Inconvenient Truth, but it definitely does not make the claim that global warming is behind all the crazy weather. See above for the distinction between climate and weather.
Speaking of which, Geoffrey -- early springtimes are presumably more than a climatic trend than a weather trend, so this observation raises valid questions about global warming. As to whether we should just be grateful for the hot weather if it raises people awareness...tough call. This knife cuts both ways. But if Congress decides to act because the cherry trees are blooming in DC, I suppose it would be churlish not to consider the early spring a blessing.
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1st winter in my lifetime (57 years) when we had to wait until end of January for ice fishing.
Hope to go this weekend for 1st time this winter!
Also, almost no snow. Lakes seem to be freezing later and later.
Worcester, Mass.
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