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skamble

Listed below are comments made by skamble between Saturday, 4th July 2009 and Monday, 20th July 2009.

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Looking back over an action-packed odyssey 9:41pm on 20 Jul 2009 I would like to re-post a comment that I put earlier in the "Are we all doomed?" blog.

The reason is that I posted it there too late, and it did not attract much attention. This comment deals with the worst possible case of greenhouse effect, and here it is:

Are we all doomed?

There is only one scenario of climate change that is a cause for concern about more than a major inconvenience for people. It is the possibility (or impossibility?) of water temperatures at large depths rising by two or three degrees and causing the escape of methane stored as methane hydrates in such a way that it takes place not over several centuries, but over several decades.

The half-life of the molecule of methane in the atmosphere is about 10 years. If the speed of the release is comparable to this, then one has to take into account that methane absorbs the infrared 60 times stronger than carbon dioxide.

The quantities of methane stored at large depths as methane hydrate ice are immense but they are spread over very large areas. This makes it not likely that it will all escape at the same time.

But if methane will escape over a short period of time, as a result of some downward warm current causing the methane hydrates to bubble out,
this may push the atmosphere into a state that was never experienced before.
The modern world intrudes on the Amish 9:32pm on 20 Jul 2009 I wonder what do the Amish use for lighting.

If they use candles or kerosene lamps, it would produce much more carbon dioxide per household than electric lighting. Probably hundreds or thousands times more than someone who uses LED lights.

It seems to me the challenge is to cut greenhouse emissions, not to go back in time.
Looking back over an action-packed odyssey 11:14pm on 13 Jul 2009 Hi,

I redid the calculation using the NOAA ocean heat content graph at:

http://www.nodc.noaa.gov/OC5/3M_HEAT_CONTENT/

for the last ten years only and got +0.63 watts per square meter of ocean surface.

The website of the ARGO project says the deployment of floats began in 2000 and was complete by 2007. There are problems with pressure sensors
which likely provide readings of depth and it was not clear to me if the data was affected. The NOAA website mentions the use of the ARGO data.

It seems to me that since the change being measured is only about 1/30 of degree Celsius a year, any comparison with weather in the ordinary sense is misleading. The usual changes of temperature between summer and winter
are often 40 degrees or more, and even the day-night difference is huge compared with the tiny signal that is measured through the ocean heat content. Luckily the heat capacity of the atmosphere is small compared with that of the ocean and these huge changes of temperature affect the total heat content very little.

What I am trying to say by all this is that relying on common sense is completely misleading when dealing with a question that can only be answered with scientific measurements and calculations. It turns out the probes have to go down up to 2 kilometers and measure the temperature with great precision to get even an approximate answer.
Looking back over an action-packed odyssey 8:06pm on 12 Jul 2009 Hi Jack,

You are right, the graph only shows the changes in the oceans heat content but does not say anything about the absolute number, and the authors also neglected to point it out.

What would this absolute number be is also not immediately clear. One can say let's put the zero at the melting point when the water is liquid but a bit colder and it would freeze. The problem is the melting point depends on salinity and it differs from place to place.

Of course one can say, let us start counting from the absolute zero. Then the heat content would be an immense number that includes the energy needed to heat the ice by 273 degrees and then melt it.

The NODC (National Oceanographic Data Center) should have pointed it out on their website.
Looking back over an action-packed odyssey 9:11pm on 11 Jul 2009 Jack,

I did the calculation using the period from the middle of 1979 to roughly the middle of 2009, where the graph ends, and got +0.35 watt per square meter of the ocean surface. The ocean heat content reflects not all but most of the Earth's radiative balance.

Now I realize that not everyone took science at school, and physics and math are not everyone's favorite subjects. Unfortunately, these are required to understand a discussion about the heat energy coming to and from the Earth, because, since the space is empty, this heat energy can only be carried by radiation.

This graph was chosen to be mentioned on the BBC Ethical Man blog by me,
but I am very far from being its inventor. It is not any theory but measurements carried out by the US National Oceanic and Atmospheric Administration, which is a branch of the US Department of Commerce.
Now since the Obama administration is very new, most of the work was actually carried out under the Bush administration. Implying that the Bush administration chose an environmentally scary graph is much like saying they were green leftist tree huggers, which is quite the opposite of what most people think of George W. Bush and his administration.

In short, the Earth's radiative balance is a topic that belongs to science, not politics. This makes it harder to understand, but also free
of bias, because in empty space there are no politics at all.

Once satellites would be able to measure incoming and outgoing radiation precisely enough, the difference would be easy to calculate. Right now the ocean heat content is the most precise tool available.
Looking back over an action-packed odyssey 11:04pm on 08 Jul 2009 Hi Jack,

The zero is just an arbitrarily chosen number - for example, the NOAA scientists could say, let us call the oceans heat content in 1980 zero.

The changes to the heat content appears in 10^22 Joules units, but the total heat energy of the water in the oceans would be far larger than this and compared to it the changes would be tiny, so the graph would look like a flat line. A change of just a few degrees is important for people but the calculation of total heat energy involves degrees Kelvin,
where zero is at -273 Celsius. There is also energy involved in phase changes which makes it even more complicated. So it makes sense to use a scale for a graph where changes become visible.

Right now my computer and printer are not together because of a move. Once they are reconnected I'll print out the graph and do the promised calculation. Marking points on a computer screen is not a good idea.
Looking back over an action-packed odyssey 9:50pm on 07 Jul 2009 Jack,

The comparison between force-inertia and heating-heat capacity is made so often that the difference between heating and cooling is called forcing. Precisely, climate forcing is ISR-OLR, where ISR stands for incoming shortwave radiation, shortwave being mostly visible light, and OLR stands for outgoing longwave radiation, longwave meaning infrared.

The reason the same heat content appears in different years is that over that period the net forcing was zero, meaning there was as much cooling as heating. One can see there were also periods of net cooling, meaning the forcing was negative over that period. It means that the cooling trend experienced over these years was stronger than the overall heating trend.

Last time I checked it the reason for such large variations in heat forcing was the subject of intense ongoing research, and the main suspect was the ionosphere. This makes sense because it alone is capable of rapid changes depending on charged particles coming from the Sun, and these changes affect how transparent is the ionosphere in the infrared.

If you are interested there are research articles online, some of them answer the following question: water vapor is also a greenhouse gas, and warmer temperature results in increased water vapor pressure, meaning more water vapor in the atmosphere, causing more greenhouse effect, making even more water vapor in the atmosphere... In short, this is called water vapor runaway. There were calculations that found the reason
why this is impossible on Earth, unless the amount of sunlight reaching Earth increases by 10%, which will not happen in the next 100 million years, so we do not have to worry about it.

Another interesting discovery was the short-term thermostat whose reaction time is measured in hours, related to clouds, and the so called weathering thermostat, whose reaction time is thousands of years.

Lots of these articles will come up if you do a search with terms like
ISR, OLR, and SST which stands for sea surface temperature.
Looking back over an action-packed odyssey 10:33pm on 04 Jul 2009 Jack,

I just found one more graph of the total heat content of oceans, this time from NOAA, the US National Oceans and Atmosphere Administration. This time it is a direct link:

http://www.nodc.noaa.gov/OC5/3M_HEAT_CONTENT/

Now all it would take is ruler, pencil and calculator to translate the total huge number of joules into more readily understandable watts per square meter.
Are we all doomed? 10:17pm on 04 Jul 2009 Are we all doomed?

There is only one scenario of climate change that is a cause for concern about more than a major inconvenience for people. It is the possibility (or impossibility?) of water temperatures at large depths rising by two or three degrees and causing the escape of methane stored as methane hydrates in such a way that it takes place not over several centuries, but over several decades.

The half-life of the molecule of methane in the atmosphere is about 10 years. If the speed of the release is comparable to this, then one has to take into account that methane absorbs the infrared 60 times stronger than carbon dioxide.

The quantities of methane stored at large depths as methane hydrate ice are immense but they are spread over very large areas. This makes it not likely that it will all escape at the same time.

But if methane will escape over a short period of time, as a result of some downward warm current causing the methane hydrates to bubble out,
this may push the atmosphere into a state that was never experienced before.
Looking back over an action-packed odyssey 9:45pm on 04 Jul 2009 Hi Jack,

I found an article that seems to answer these questions. Here is the name of the file, and a Google search produced only one result for it:

FCXNL-09A02a-1661562-1-Obs_for_OHC_WhitePaper_v3.doc

On page 13 of this document there is a graph that shows the total heat content of oceans as a function of time, in years. To translate this to watts per square meter one would need to measure the slope and divide by the number of seconds in a year and the number of square meters either in the Earth's surface or in the surface of the oceans, depending on how the number is presented.

What is important in this graph is that it shows both a growing overall trend and also a strong variability between years. I have not pulled out my calculator yet and would like to do this calculation.

The article also mentions the Argo project.

I am curious to see how many watts per square meter will come out of this calculation. Will get back later,

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