Ocean Stored Significant Warming Over Last 16 Years: Research

Ocean Stored Significant Warming Over Last 16 Years: Research

The upper layer of the world’s ocean has warmed since 1993, indicating a strong climate change signal, according to a new study. The energy stored is enough to power nearly 500 100-watt light bulbs per each of the roughly 6.7 billion people on the planet.

“We are seeing the global store more heat than it gives off,” said John Lyman, an at NOAA’s Joint Institute for Marine and Atmospheric Research, who led an international team of scientists that analyzed nine different estimates of heat content in the upper ocean from 1993 to 2008.

The team combined the estimates to assess the size and certainty of growing heat storage in the ocean. Their findings will be published in the May 20 edition of the journal Nature. The scientists are from NOAA, NASA, the Met Office Hadley Centre in the United Kingdom, the University of Hamburg in Germany and the Meteorological Research Institute in Japan.

“The ocean is the biggest reservoir for heat in the ,” said Josh Willis, an oceanographer at NASA’s Jet Propulsion Laboratory and one of the scientists who contributed to the study. “So as the planet warms, we’re finding that 80 to 90 percent of the increased heat ends up in the ocean.”

A warming ocean is a direct cause of global sea level rise, since seawater expands and takes up more space as it heats up. The scientists say that this expansion accounts for about one-third to one-half of global .

Combining multiple estimates of heat in the upper ocean - from the surface to about 2,000 feet down - the team found a strong multi-year warming trend throughout the world’s ocean. According to measurements by an array of autonomous free-floating ocean floats called Argo as well as by earlier devices called expendable bathythermographs or XBTs that were dropped from ships to obtain temperature data, ocean heat content has increased over the last 16 years.

The team notes that there are still some uncertainties and some biases.

“The XBT data give us vital information about past changes in the ocean, but they are not as accurate as the more recent Argo data,” said Gregory Johnson, an oceanographer at NOAA’s Pacific Marine Environmental Laboratory. “However, our analysis of these data gives us confidence that on average, the ocean has warmed over the past decade and a half, signaling a climate imbalance.”

Data from the array of Argo floats­ - deployed by NOAA and other U.S. and international partners ­- greatly reduce the uncertainties in estimates of ocean heat content over the past several years, the team said. There are now more than 3,200 Argo floats distributed throughout the world’s ocean sending back information via satellite on temperature, salinity, currents and other ocean properties.

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May 19, 2010
So argo data are more reliable and show cooling trend. A number of skeptics websites noticed it, and the news were all over the net. I assume this is an obligatory believers "rebuke", slowed down by inertia of traditional publishing venue.

May 19, 2010
Tegiri: Interesting post. You send us to a site that has banners for the end of the world in 2012 and talks about how difficult it is to get ARGO data. So, I figured I would try. First I used Google to look up the Argo site:


I then read the instructions on Argo data and how to get it and that sent me to:


And, guess what? From there you can get any of the Argo data sets. I think I will take NOAA's analysis and data over that of a 2012 Armageddon site. I suggest you go take a look at the article again and realize this is a real step forward in identifying trends in data (you know, data is that stuff that does not point toward the world ending in 2012). :-)

May 19, 2010
Not to mention that Global Research, while not totally devoid of merit, has a notoriously lax editorial policy, and is therefore frequently host to the most egregious spinsters imaginable.

May 19, 2010
I pulled out the first article that showed up in google, admittedly not the best one. However at the link you provided there is a curious page
In 2008 somebody averaged the data, and plotted a gray curve that evidenced cooling thrend. Apparently, this deviation out of the party line made many unhappy, and they didn't hesitate to come up with an adjustment (black line). Hillarious!

May 19, 2010
You referring to this one?


I don't see what's so "Hillarious!" about compensating for systematic XBT biases. But maybe there's some subtlety that I've missed, which you found so amusing. In which case, I await enlightenment, with baited breath.

By the way, the "heat content" curve (Figure 4) in your first link, looks suspiciously similar to the *sea level* curve (Figure 2) from the argo site. Now THAT's "Hillarious!"

May 20, 2010
{is constantly amused by people who await events with baited rather than bated breath} :-D

May 20, 2010
"since seawater expands and takes up more space as it heats up"

That's not right. Water is most dense around 4 degrees C, and it expands both when it is warmed AND when it is cooled by a non-linear factor. The rate of expansion is zero around 4 degrees C and increases in both directions from there. NOAA's web site says ocean surface temp has increased from 13.13 C to 14.5 C (1.37 C increase). At that temp range the expansion coeff is apx .00019. So assuming that the 2000 m of surface water they describe above increased by 1.37 C and ocean surface area of 361 million sq km, that yields a .52 meter rise in sea level. Since we aren't drowning yet, I assume I am over-simplifying this. My point is that the story is also over-simplifying things a little bit. Just give them more funding so they can do thier research and please ask them to stop publishing alarmist news stories.

May 20, 2010
Interesting post. You send us to a site that has banners for the end of the world in 2012

This site has ads for 2012 garbage on it quite often as well. Thermo, that was a bad nonargument.

The rest of your post was on the money.

Since we aren't drowning yet, I assume I am over-simplifying this.

Yes, greatly. There's multiple other processes and the fact that water is no homogenouos in heat content that skews your calculations. The article doesn't give much to go on though.

May 20, 2010
"The article doesn't give much to go on though."

Now that sums it up quite nicely. lol, yes, my cherry-picking of the worst data I could find from their own web site and the gross over-simplification for my calculation was deliberate. I was just making the point that if they want to leave out a bunch of details and cherry-pick factoids then so can I. The most interresting part of this story is probably the details behind the comment "there are still some uncertainties and some biases". I'm also not sure about using such a short time span for climate trending and predictions. I'm really skeptical about any length of time shorter than 100 years and somewhat skeptical of anything less than 1000 years. The noise factors in temperature and sea level are huge on short time scales. They surely need to be making observations, which they are, but making predictions with so little data is more than a little bit dubious.

May 20, 2010
{is constantly amused by people who await events with baited rather than bated breath} :-D
Touche. In my defense, I'm slightly dyslexic, and sometimes my brain runs scripts that I'm not consciously invoking. I always go over my posts before I submit them, but am nonetheless periodically amused to discover -- after the fact -- that I managed to make a perfectly symmetrical transcription error both while typing, and while later reading back what I've typed.

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