Climate and weather are hot topics these days. As you read about them one factors looms large for the coming months: The odds are increasing that an El Niño is in the works for 2014—and recent forecasts show it might be a big one. Others have probably written about this but I am reading Six Degrees: Our Future on a Hotter Planet by Mark Lynas and am in a frame of mind that finds the forecast in he above link even more troublesome.
So I snooped around a bit and came across a nice "primer" on El Niño That helps your understanding if you need it. From he first link:
As we learned from Chris Farley, El Niños can boost the odds of extreme weather (droughts, typhoons, heat waves) across much of the planet. But the most important thing about El Niño is that it is predictable, sometimes six months to a year in advance.
That’s an incredibly powerful tool, especially if you are one of the billions who live where El Niño tends to hit hardest—Asia and the Americas. If current forecasts stay on track, El Niño might end up being the biggest global weather story of 2014....
A recent reversal in the direction of the Pacific trade winds appears to have kicked off a warming trend during the last month or two. That was enough to prompt U.S. government forecasters to issue an El Niño watch last month.
So if this interests you please read on and we will explore the possible consequences.
From the second link:
The twists and turns in the ongoing dialogue between ocean and atmosphere in the Pacific can have a ripple effect on climatic conditions in far flung regions of the globe. This worldwide message is conveyed by shifts in tropical rainfall, which affect wind patterns over much of the world. Imagine a rushing stream flowing over and around a series of large boulders. The boulders create a train of waves that extend downstream, with crests and troughs that show up in fixed positions. If one of the boulders were to shift, the shape of the wave train would also change and the crests and troughs might occur in different places.
Dense tropical rainclouds distort the air flow aloft (5-10 miles above sea level) much as rocks distort the flow of a stream, or islands distort the winds that blow over them, but on a horizontal scale of thousands of miles. The waves in the air flow, in turn, determine the positions of the monsoons, and the storm tracks and belts of strong winds aloft (commonly referred to as jet streams) which separate warm and cold regions at the Earth's surface. In El Niño years, when the rain area that is usually centered over Indonesia and the far western Pacific moves eastward into the central Pacific, as shown here, the waves in the flow aloft are affected, causing unseasonable weather over many regions of the globe.
The impacts of El Niño upon climate in temperate latitudes show up most clearly during wintertime. For example, most El Niño winters are mild over western Canada and parts of the northern United States, and wet over the southern United States from Texas to Florida. El Niño affects temperate climates in other seasons as well. But even during wintertime, El Niño is only one of a number of factors that influence temperate climates. El Niño years, therefore, are not always marked by "typical" El Niño conditions the way they are in parts of the tropics.
That doesn't sound too bad for us. Yet the first link expresses other concerns:
As I wrote last fall, the coming El Niño could be enough to make 2014 the hottest year in recorded history, and 2015 could be even warmer than that. The 1997-98 super El Niño was enough to boost global temperatures by nearly a quarter of a degree Celsius. If that scale of warming happens again, the world could approach a 1ºC departure from pre-industrial times as early as next year. As climate scientist James Hansen has warned, that’s around the highest that temperatures have ever been since human civilization began.
Indeed, even the forecast is already having an effect: An index of global food prices reached a 10-month high in March, blamed in part on shortages an El Niño may exacerbate. Here’s what else we could expect:
A severe drought continues to rage in and around Indonesia, which an El Niño would likely worsen.
Peru’s anchovy catch may be significantly affected should a strong El Niño materialize.
Australia’s ongoing battles with bush fires may be intensified once its dry season resumes later this year.
But perhaps the strangest impact so far has been in India, where monsoon forecasting is at the heart of national politics. The meteorology department there has accused U.S. weather forecasters of “spreading rumors” and colluding to ruin the Indian stock market by forecasting a return of El Niño.
There is lots more to this, but this should suffice to get people's attention.
Some other
There’s a bit of good news, too: Hurricane seasons in the Atlantic tend to be less severe under this kind of forecast. And people in drought-stricken California could be forgiven if they’re crossing their fingers for a strong El Niño, which is linked to some of the wettest years in state history. Still, it’s certainly no slam dunk that an El Niño would be enough to end the crippling drought there or even bring above normal rainfall. And if the El Niño ends up being as strong as current predictions indicate, there’s a chance it may even tip the scales from drought to deluge across the state, spurring damaging mudslides amid bursts of heavy rain. The two strongest El Niños in the last 30 years—1982-83 and 1997-98—both caused widespread damage from flooding in California.
The moral of the story here is: Be careful what you wish for.
So we can use this weatherman to tell us about how the winds are blowing and what it may mean or future months.
Sun Apr 27, 2014 at 10:33 AM PT: thanks for putting this on the rec list.