Image: Courtesy of NOAA-NASA GOES Project
In Brief
- The tropical rain band that wraps the globe north of the equator migrates as atmospheric temperature changes, altering rainfall patterns worldwide.
- Data from sediments in Pacific Island lakes show that the band is at 3°N to 10°N, as far north as it has ever been in at least 1,200 years.
- At current warming rates, the band could shift north by five degrees by 2100, drying out farmland for millions of people in Ecuador, Colombia and elsewhere.
- Multiyear drought conditions in the southwestern U.S. could persist as that area becomes more like the semiarid region of northern Mexico.
More In This Article
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Photo Album
Where Will the Rain Fall in 2100? [Slide Show]
The first indication that our expedition was not going as planned was the abrupt sputter and stop of the boat’s inboard engine at 2 a.m. The sound of silence had never been less peaceful. Suddenly, crossing the open ocean in a small fishing vessel from the Marshall Islands in the North Pacific Ocean seemed an unwise choice. A journey to a scientific frontier had led us to a different frontier altogether, a vast darkness punctuated by the occasional lapping wave.
We are climate scientists, and our voyage (which ended safely) was one of many intended to help us do what at first glance seems impossible: reconstruct rainfall history back in time, across an ocean. By tracing that history, we can gain a better understanding of how the ongoing buildup of greenhouse gases in the atmosphere, rising air temperatures and changes in tropical precipitation are likely to alter future climate patterns. We have traveled far and wide to numerous islands across the Pacific Ocean.
This article was originally published with the title A Shifting Band of Rain.
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7 Comments
Add CommentI hardly know where to start with how bad this article and research is, and how much guts it to took to print it by Scientific American. Julian Sach and his photo-shoot friend Myhrvold try hard to put one over on the scientific community. They think that by using a ten-foot tube to get a six-foot core sample out of an equatorial heat island that their data will not be biased. If you only measure equatorial heat islands, you will only get increased temperature effects, no matter what D/H algae lipid levels are measured. Where's the 3000-foot lake to compare with? The research is biased before it even starts. I commend the authors that they do give some credence to solar activity but their heart isn't in it. In 1983, Denmark's Willi Dansgaard and Switzerland's Hans Oeschger drilled two Greenland ice cores one mile deep, one mile apart, representing 250,000 years of the Earth's layered climate history. The cores were laid side by side. They found a 2500 year cycle superimposed on the big, ice age, climate swings. Their report in 1984 linked that cycle to the cycles of the Sun. These cycles also noted that it was before CO2 became an issue on this planet. Now, those cores were true research....not the flim-flam 6-foot cores that the authors are trying to promote to get tenure.
Reply | Report Abuse | Link to thisThe authors use an undocumented "hockey stick" graph. I have seen many "hockey stick" graphs but theirs have a pronounced uptick at the end. Where did they get their graph? None of the IPCC graphs have such a pronounced uptick. The authors refer us to a Michael E. Mann article. They surely know that Michael E. Mann and his cohort Phil Jones are the originators of emails discovered by hackers showing that both of these idiots tried to hide climate data that show just the opposite of global warming. Michael Mann is also the originator of the "hockey stick" graph that has been disproven statistically and by his un-disclosed use of urban heat islands to measure tree rings. Also, their graph deletes the Roman Warming cycle that shows termperature that is even warmer than the Medieval Warming.
The authors describe data from "colleagues" that they want to correlate with. That means that they want to find facts that don't rock the boat on global warming. The authors research is doomed from the beginning. It isn't true, unbiased research. It is research trying to promote global warming from the get-go. Their shifting band of rain will change and change again. It has nothing to do with man-made global warming. It's the sun, stupid!
Your reply is the most cogent well written part of this whole article. Thank you for responding so intelligently.
Reply | Report Abuse | Link to thisIt is not surprising that rain band are shifting poleward; although this study touches only on the northern hemisphere. Climate models predict that Hadley cells will get larger as the temperature increases, and here, lo and behold, we have yet more evidence that the people writing the models do indeed have a clue about what they are doing.
Reply | Report Abuse | Link to thisReally hate to "rain" on your parade guys BUT;
Reply | Report Abuse | Link to thisThe Earth in its orbit around the Sun both magnetically interact giving us our Seasons.
Normally there are two “dramatic” Earth tippings a year.
One in late summer or fall when the Suns north magnetic pole severs with the Earths north magnetic pole and one in late winter or early spring when the Suns south magnetic pole severs with the Earths south magnetic pole.
The cause of Earth Changes is the erratic movement of Earth on its's meandering magnetic axis changing it's exposure to both Sun and Moon.
The date, time and distance of these tippings (magnetic pole movement) is at this time crucial and I’ll explain it this way.
When the Earth tipped that one thousand miles it moved the magnetic pole location one thousand miles in the opposite direction moving the Equator (Sun exposure) one thousand miles. Last winter Russia was getting the cold from the closer pole and loosing the heat of Sun exposure. This year its opposite.
This is real important Stuph and all we need is to have some one monitor these tippings. We would then know what and where crops should be planted, where to plan our skiing etc.
Like I say we really need some one to take charge and properly monitor Magnetic Pole Movement. Believe me its for the good of OUR WORLD!
cbc.ca bruce voigt
The rain band in the Southern Hemisphere must have moved down to my latitude of 38
Reply | Report Abuse | Link to thisdegrees as it now rains a lot in the summer.
Well it rains more in my little world more than years ago,and like most people I only worry about my patch.
I know I have to mow the bloody lawn again tomorrow!
The full print article, with several diagrams and more on their methodology, is missing from this on-line link. Attempts to access the full article on the web from here did not prompt so much as an invitation to subscribe, so I am disappointed.
Reply | Report Abuse | Link to thisIn print, they reported that the location of the rain band fluctuates between winter and summer. Also in print, the authors made a connection to drier seasonal weather in the coffee-growing countries of Colombia and Ecuador.
I would also recognize that the authors do not necessarily mean that the "rain bands" are linear phenomena, but we know that the jet stream wanders about. We also recognize that the movement of the "rain bands" could produce precipitation in places which have been historically dry, like some deserts which show historic records of greater precipitation. Also, the limited data is interesting but insufficient in my estimate to validate a need for some corrective action on the part of world governments. It is data, not necessarily information of great value.
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