Dr. Roy Spencer presents the latest measurements of lower troposphere temperature as measured by two sets of satellites. See his post here. He presents a graph showing measured temperatures versus model predictions.

You can see that actual global temperatures have flattened out since about 1998. The “spaghetti” on the graph represents predictions of 44 models and the black line is the average of model predictions.

Spencer presents three possible explanations for the divergence:

“1) the real climate system is not as sensitive to increasing CO₂ as the models are programmed to be.” (His preferred explanation).

“2) the extra surface heating from more CO₂ has been diluted more than expected by increased mixing with cooler, deeper ocean waters (Trenberth’s explanation)”

The oceans have a high heat capacity and can absorb great quantities of heat. But have they? The subject is controversial. Anthony Watts discusses the problem here. He notes a recent study which says that between 1955 and 2010, the temperature of the global ocean, between the surface and a depth of 2,000 meters increased in temperature by 0.09 C. That’s not much and Watts wonders if we can even measure to that precision.

“3) increased manmade aerosol pollution is causing a cooling influence, partly mitigating the manmade CO₂ warming.”

However, a 2007 satellite-based NASA study shows that aerosols have been decreasing steadily since 1992. In particular, sulfate aerosols have been greatly decreasing since establishment of the 1970 Clean Air Act in the U.S. and similar measures in Europe.

Explanations #2 and #3 seem to have problems. That leaves #1: the climate is not very sensitive to carbon dioxide and is much less sensitive than models assume. The forcing effect of carbon dioxide, if any, is apparently easily overcome by stronger natural forces.

If Spencer’s first explanation is correct, the political war on fossil fuel emissions is futile and will have little or no effect on global temperatures, but that war will cost us dearly by raising energy prices and making our electric grid less reliable.

See also:

Global warming theory fails again

Failure of the Anthropogenic Global Warming Hypothesis

Methane hydrate is a solid substance in which methane (natural gas) is trapped in the crystal structure of ice. Methane hydrate occurs in marine sediments and crops out on the ocean floor where the pressure is sufficiently high and the temperature is sufficiently low. Technically, methane hydrate is called a clathrate which means that water molecules freeze into a lattice-like structure capable of trapping gas inside. These compounds can also occur in permafrost. The methane is produced from microbial decomposition of plankton which sinks to the ocean floor. See a short explanation from the U.S. Geological Survey (USGS) here. See also an article at Geology.com here. The map below shows the estimated global distribution of methane hydrates.

Estimates of the total resource vary widely. Gas units are often given in units of one trillion cubic feet (TCF). The USGS says that resources estimates from studies over the last 15 years vary from one million- to fifty million TCF of natural gas. The lower estimate is more than 4,000 times the annual US consumption of natural gas. The lower estimate is also at least twice as much as all other fossil fuels combined.

The big question now is: can these resources be technically and economically recovered?

Last year, the Department of Energy partnering with ConocoPhillips and Japan Oil, Gas and Metals National Corp. produced a steady flow of natural gas in the first field test of the new method that injects carbon dioxide into Alaskan permafrost. The carbon dioxide replaces the methane in the clathrate structure.

Last month, Japan became the first country to extract natural gas from methane hydrates in the sea bed. (See story in The Asahi Shimbun here.) According to that story, Japan Oil, Gas and Metals National Corp. was able to extract natural gas from a layer 330 meters below a 1,000-meter-deep floor of the Pacific Ocean. Water was pumped out of the methane hydrate sediment layer causing a drop in pressure which liberated the gas. Methane was collected by pipes. The Japanese government plans to establish production technology by fiscal 2018 and then begin production. “The seas around Japan are estimated to hold enough methane hydrate to produce as much natural gas as Japan consumes in 100 years.”

This is still emerging technology that could hold great promise, similar to the vast new resources made recoverable by the “fracking” revolution in shale oil and gas.

See also:

Geologic History: PETM when it really got hot

Methane hydrates probably played a part in the Paleocene-Eocene Thermal Maximum (PETM) which was a global temperature spike that happened about 55 million years ago.

It is the stated policy of the federal government, and some state governments, to replace use of fossil fuels with alternative energy, especially in the production of electricity. The stated rationale for this policy is to reduce carbon dioxide emissions and lessen our dependency on imported fossil fuels. Several states (including Arizona) have laws which mandate that a certain (increasing) percentage of electricity be produced with the usually much more expensive alternative energy sources such as solar and wind generation. How well is that working?

A study published earlier this year asked: “Do alternative energy sources displace fossil fuels?” The answer is “not much.”

Richard York of the University of Oregon studied the use of alternative energy in 130 countries to assess the contribution of various forms of non-fossil fuels. The study showed “that the average pattern across most nations of the world over the past fifty years is one where each unit of total national energy use from non-fossil-fuel sources displaced less than one-quarter of a unit of fossil-fuel energy use and, focusing specifically on electricity, each unit of electricity generated by non-fossil-fuel sources displaced less than one-tenth of a unit of fossil-fuel-generated electricity.”

Nuclear and hydro generation were the best of the alternatives to fossil fuels. Each kilowatt-hour (kwh) of nuclear generation of electricity displaced about 0.2 kwh of fossil fuel generation; hydro displaced about 0.1 kwh. Wind and solar generation did not displace any fossil fuel generation.

There are two reasons for that last result. First, wind and solar generation, while increasing, still represent a very small part of the generation capacity compared to consumption. But the main reason for lack of impact of solar and wind generation is that they are unreliable, intermittent sources that require backup generation, and that is usually by fossil fuels. Furthermore, because the fossil fuel backup generation must be on-call, it cannot run efficiently and therefore it actually uses more fuel than it would had it been the primary source. And incidentally, the backup generation also produces more carbon dioxide emissions than it would have had it been run efficiently as primary generation.

York concludes: “These results challenge conventional thinking in that they indicate that suppressing the use of fossil fuel will require changes other than simply technical ones such as expanding non-fossil-fuel energy production.”

See also:

The scale problem for solar and wind generation of electricity

Renewable energy mandates raise electricity costs

Renewables receive bulk of tax preference subsidies

Electricity generated by wind power may raise temperatures and costs

Wind farms raise local and regional temperatures

Blowing in the Wind, a look at green jobs

EIA says Clean Energy program will increase electricity costs 29%