World Grain - January 2020 - 66

INDONESIA

SEEING MORE
RAINFALL

Change in ocean temperature may also bring more rain to Australia
by Drew Lerner

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Long before you can see the steam there is a steadily
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into the atmosphere. Air that becomes warmer than its
surrounding air will rise because it becomes less dense.
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atmosphere along with the warming.
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the body of water, thereby reducing the weight of air
pressing downward on the surface of the water. That
is all that a low-pressure center is - just rising air. If
you take the same principle out to the ocean and warm
a super large area of ocean water, you release water
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you create a low-pressure center.
Today's warm ocean water in the Gulf of Alaska has
created a large region of low pressure with abundant
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across the warm body of water, they tend to intensify
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Alaska and the added moisture rising in the atmosphere
sets the stage for greater storminess once the warm,
moist, air reaches a certain altitude when it meets colder
air aloft. The dynamics in the atmosphere then become
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er air aloft and substantial rain falls downstream from
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usual ocean body. Hence, the warm Gulf of Alaska this
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and brought drought conditions down in many areas.

©Alex - stock.adobe.com

cientists continue to learn more about our oceans
and atmosphere and how they interact with each
other. Back in the infancy of this meteorologist's
career in the late 1970s, we had little to no clue just
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was all about ENSO (El Niño Southern Oscillation - including El Niño and La Niña). But now it is becoming
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can radically change weather.
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home with huge regions of anomalous ocean temperaWXUHLQYDULRXVSODFHVLQWKHZRUOGUHVXOWLQJLQXQXVXDO
weather. One such region was in the Gulf of Alaska
in 2017 and 2018 when a super large region of cool
ocean water, similar to that which occurred in 1988,
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ing rainfall just like in the past. Drought that began in
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early 2019, but that unusually cold ocean water anomaly in the Gulf of Alaska translated into a huge region
of warmer ocean water in 2019 and it remains there
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in the summer of 2019 and it is predicted to fall away
completely in 2020 because of the warm water bias.
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a body of water, no matter how slight the warming is,
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in your kitchen when you start to boil water. As the pot
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not see it until the pot of water becomes exceptionally

66

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