Tuesday, November 18, 2014

Third Quarter Ocean Warming is 200% above Trendline

The ocean heat content numbers are in for the third quarter -- and they again show big increases.

For the 0-700 meter region, the change from a year ago is 0.59 W/m2 (the area being the total Earth's surface).

That's over twice as large as its trend over the last 15 years, which is 0.28 W/m2.

For the 0-2000 m region, the change from a year ago is 1.73 W/m2, whereas its trend since its data started in 2005 is 0.58 W/m2.

The top half of the ocean gained 200% more heat than it has on average.


For the top 2000 meters, a quadratic fit is again better than a linear fit, with the acceleration being 0.07 W/m2 per year.


Saturday, November 15, 2014

When Just a Littllllllllle More Heat Goes Into the Ocean (Re: Hiatus)

There's an nice article in NCSE Reports by John Abraham, John Fasullo and Greg Laden, titled "Continued Global Warming in the Midst of Natural Climate Fluctuations," about the hiatus and all that. It's not very technical and would be a good thing for those who think the hiatus means no more global warming to read.

The first figure in the article (right) reminded me of something I've been wondering -- how sensitive are atmospheric trends to changes in the 93.4% number for the percentage of heat that goes into the ocean?

I think I can estimate it with some simplications. The answer is, if I'm right: surface and tropospheric temperature trends are very sensitive to changes in ocean heating. Answer below (in red), using some very basic physics that is a bit pedantic.

Let Qin be the amount of heat coming into the Earth over some period of time. (So the units of Qin are energy per unit time, whereas the symbol Q is usually used for just energy.) Let's assume in all goes either into the ocean or into the troposphere, so Qin = QO + Qt, where QO is the amount of the heat that goes into the ocean, and Qt the amount into the troposphere.

Now consider two scenarios. In the first, the one we're living in, a fraction f1 (= 0.934) of the heat goes into the ocean, and in the second, a fraction f2 goes into the ocean.

So
QO,1 = f1Qin and QO,2 = f2Qin.

By assumption, the total amount of heat going into the Earth is the same, so

Qin = QO,1+ Qt,1 = QO,2 + Qt,2

where "t" stands for troposphere. A dash of rearranging and a smidgen of algebra gives

(f1-f2)Qin = Qt,2 - Qt,1

What is Qin? It's QO,1/f1. We know what f1 is: 0.934, from the figure. If we assume all the heat coming into the ocean goes into the 0-2000 m region (that's the top half of the ocean -- and not a bad assumption), then QO,1 can be estimated from 10-years worth of Argo data for that region. When I do that I get 0.93e22 J/yr.

That finishes the ocean part. For the troposphere

Q1 = mtctΔT1 and Q2 = mtct ΔT2,

where ΔT is the amount of temperature change from whatever the baseline is:  ΔT1 = T1 - Tbase and likewise for scenario 2. (Strictly speaking it's the change of temperature with time, viz. a trend, but as with Q above I'll just call it T.) Then


Qt,2 - Qt,1 =  mtct (T2 - T1)

where we want to calculate the temperature difference as a function of f2. 

Putting this all together then gives

T2-T1 = (1-f2/f1)QO,1/mtct

All this would surely look better if (1) I knew more HTML, and (2) I was using Wordpress, which has an equation-maker plug-in, but I don't and I'm not.

Now, what's the mass of the troposphere? About 80% of the total atmospheric mass, or 4.1e18 kg. 

(Interestingly, you can calculate the atmosphere's mass without leaving your chair: m = PsA/g, where Ps is the surface pressure, A is the Earth's area, and g the acceleration due to gravity at the surface. Of course, g varies with altitude, but that's a small effect.)

Here ct is the troposphere's specific heat. I'll assume the troposphere is homogeneous throughout, and approximate its specific heat by the specific heat of air at typical room conditions and 40% humidity, which is 1,012 J/kgK.

Now we just calculate. If f2 = 0.935 -- that is, it's just 0.1 percentage points above f1 -- I find the difference in trends is


T2-T1 = -0.024°C/decade

which seems like it could be in the ball park. At least, it doesn't seem ridiculous. And the sign is right: more heat into the ocean means heat taken out of the troposphere, which lowers its temperature.

So a very small change in how much heat goes into the ocean can lead to noticeable changes in the temperature trends. If f2 is 0.5 percentage points above f1, then 

T2-T1 = -0.12°C/decade

which could well put a damper on the greenhouse warming of a decade or two. So just a little more heat going into the ocean (relatively little -- it's still a huge number of Joules) can noticeably cool the troposphere. Or even more noticeably for the surface, which holds even less heat then the troposphere (for, say, the top 2 meters of air above the surface).

That's what I suspected, and the rough numbers seem to support that.

Friday, November 14, 2014

When U Thant Was Overly Dramatic

"I do not wish to seem overdramatic, but I can only conclude from the information that is available to me, that the Members of the United Nations have perhaps ten years left in which to subordinate their ancient quarrels and launch a global partnership to curb the arms race, to improve the human environment, to defuse the population explosion, and to supply the required momentum to development efforts. If such a global partnership is not forged within the next decade, then I very much fear that the problems I have mentioned will have reached such staggering proportions that they will be beyond our capacity to control."

-- U Thant, Secretary General of the United Nations, 1969, from the Introduction to The Limits to Growth (pg 14).
The authors then give this projection, and we're at the apex about now:


On the other hand, they were remarkably accuate with their CO2 projection; the atmospheric CO2 value for January 2000 at Mauna Loa was 369 ppm:

As Wikipedia says, "the book continues to generate fervent debate...," and I'll leave it at that.

Kim Kardashian and the Laws of Physics

#kimkardashian
Excuse me, but this picture of Kim Kardashian, impressive though it may be, violates the laws of physics. (And no, I don't mean her posterior projection, I mean the trajectory of the champagne stream. Though maybe her derriere is photoshopped too.)


GISS Gallop

NASA GISS's global temperature anomaly last month was the highest October in their records, and the 7th-warmest month ever, tied with last month.

That's the third month in a row it's set a record, for that month. (Since they're anomalies, any month can be compared to any other month, regardless of whether it has the same name, but comparing them by month is (1) fun, (2) a reminder that it's still warming.)

Here's how 2014 compares to the commodious capacious big 1997-98 El Nino. The Nino3.4 index is finally increasing, but still way behind the Big One. Yet the surface temperatures for the year-so-far are much higher, an average of 0.24 C higher. (So since it's 17 years later, a crude estimate of the trend from then to now would be 0.24°C/17 years = +0.14°C/decade.)


Here's the warming from any given year to today. The total warming according to GISS is now +0.88°C, which rounds to 0.9°C, instead of the "0.8°C" you usually see quoted. Update your vocabulary.


Monday, November 10, 2014

Climate Scientists Get Their Own Lawyer

From the Climate Science Legal Defense Fund:
Lauren KurtzTo all our supporters,

“After years of attacks, I am thrilled that there is a world class litigator whose full time job is to stand up for scientists.” –Dr. Michael Mann, Distinguished Professor of Meteorology at Penn State

The Climate Science Legal Defense Fund is excited to announce the hiring of Lauren Kurtz as its first Executive Director. Thank you to everyone who donated money to the fund and made this possible. Her first day is today and feel free to reach out to her with thoughts, ideas and words of encouragement as she takes on the important job of defending the scientific community from politically motivated attacks. She can be reached at lkurtz[at]climatesciencedefensefund.org

Lauren is joining CSLDF from Dechert LLP, a top tier law firm after a multi-month hiring process. At Dechert she served as project manager on a high-profile $3 billion litigation initiative and she represented commercial and individual clients on cases involving FOIA requests and litigation over FOIA requests, discovery disputes, and defamation claims. Prior to working at Dechert, she held legal and policy positions at the U.S. Environmental Protection Agency. She has a law degree from the University of Pennsylvania Law School and a master's in Environmental Policy from the University of Pennsylvania. She will be based in NYC working in an office generously provided by the Sabin Center for Climate Change Law at the Columbia Law School.

Thank you again for all your support,

The Climate Science Legal
Defense Fund Board of Directors
www.climatesciencedefensefund.org
Here are some profiles of Lauren Kurtz: Linked In, Law360, State Bar of California, I hope she is prepared for an onslaught by the crazies.

Does any other scientific field have its own lawyer(s)?

Sunday, November 09, 2014

Stephen Schneider on Uncertainty

"I readily confess a lingering frustration: uncertainties so infuse the issue of climate change that it is still impossible to rule out either mild or catastrophic outcomes, let alone provide confident probabilities for all the claims and counterclaims made about environmental problems."

-- Stephen Schneider, Scientific American (2002)
which is quoted in this paper which is interesting reading: "How science makes environmental controversies worse," Daniel Sarewitz, Environmental Science & Policy 7 (2004) 385-403.