Pacific sea level predicts global temperature changes

From University of Arizona:

IMAGE: The Jason series of US/European satellites can measure the height of the ocean surface. view more

Credit: NASA/JPL-Caltech

The amount of sea level rise in the Pacific Ocean can be used to estimate future global surface temperatures, according to a new report led by University of Arizona geoscientists.

Based on the Pacific Ocean’s sea level in 2015, the team estimates by the end of 2016 the world’s average surface temperature will increase up to 0.5 F (0.28 C) more than in 2014.

In 2015 alone, the average global surface temperature increased by 0.32 F (0.18 C).

“Our prediction is through the end of 2016,” said first author Cheryl Peyser. “The prediction is looking on target so far.”

Scientists knew that both the rate at which global surface temperature is rising and sea level in the western Pacific varied, but had not connected the two phenomena, said Peyser, a UA doctoral candidate in geosciences.

“We’re using sea level in a different way, by using the pattern of sea level changes in the Pacific to look at global surface temperatures – and this hasn’t been done before,” she said.

Peyser and her colleagues used measurements of sea level changes taken by NASA/NOAA/European satellites starting in 1993.

Using sea surface height rather than sea surface temperatures provides a more accurate reflection of the heat stored in the entire water column, said co-author Jianjun Yin, a UA associate professor of geosciences.

“We are the first to use sea level observations to quantify the global surface temperature variability,” Yin said.

The team found when sea level in the western Pacific rises more than average — as it did from 1998 to 2012 — the rise in global surface temperatures slows.

In contrast, when sea level drops in the western …

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