Friday, September 04, 2009

Sea Levels

More context for the boondoggle known as climate change.

Rising sea levels a sign of runaway global warming, which will doom us all?

For some perspective, a longer-term chart:

An observer makes these cogent remarks about the graph:

As it happens, the IPCC does present a chart of sea levels and its trend is more obvious than the temperature trend. It shows a steady rise of about 200 millimeters in the last 120 years. That's about eight inches. Is eight inches over 120 years significant or alarming?
First, look at the vertical scale. It ranges over about 120 meters (not millimeters), about 400 feet. On the page you see this graph, a change of 200 millimeters (or the change in the last 120 years per the IPCC) would be would be about the width of your eyelash. When the seas were 400 feet lower, people could walk from Russia to Alaska and from France to England.

We engineers have a saying: measure with a micrometer, mark with chalk, cut with an axe. That saying is meant to put things in perspective for young engineers who like to calculate things out to the number of digits visible on their calculators.

Global warmists are taking their micrometer, literally, to the last 120 years on this chart, an area that would probably fit in the upper rightmost dot on that chart. And from that, extrapolating that we are all about to die.

I no longer need to squint my eyes to see a one degree per century trend in a cloud of noisy data. The trends are stark. Thus, my epiphany.

If sea levels go along with global temperatures, as the warmists frequently remind us, then this chart makes blatantly obvious that

-- Man has just about nothing to do with global temperatures,
-- Any temperature changes in the last 100 years are insignificant compared to longer term changes,
-- And current trends are most likely just the final flattening out of temperatures after rising from the last ice age.

How can you blame man for sea levels rising when about 99% of that rise since the last ice age occurred before man built the pyramids, much less SUVs? A rise in sea level over the last century should not be surprising; it's been rising for the last 20,000 years.
More inconvenient questions from this author:
I've seen graphs of temperatures, such as the so-called "global" temperature. The UN's Intergovernmental Panel on Climate Change, for example, presents such a graph in its "Summary for Policy Makers." While this graph does present to the eyeball a rising trend, one could ask several questions.

The total range of temperatures is within plus or minus half a degree Centigrade. Are we sure we are seeing a true trend and not just randomness?

The total range of time is about 150 years, and the range of time in which an upward trend is apparent is perhaps the last 30 years. Is that a long enough time period to gauge a trend?

On the other hand, looking closely at the years since 1998, the trend seems to have leveled off or even dropped. Is that too short a time to gauge a trend?

Are the thermometers in enough places and the right places? Maybe we get too many readings from North America and too few from Antarctica, for example.

How do you get just one number for each year? How do you take all the temperature readings from all the thermometers and all the days and hours that temperatures were read, and get a single number?

If a computer algorithm is used to come up with the numbers, how sure are you that the algorithm did not add some artificial biases?

How do you compare temperatures over time? Weren't thermometers added, thermometers replaced, and whole new stations included? Are earlier readings comparable with later ones?

How do you know any given temperature reading reflects real climate, and not just what's happening near that temperature station? That is, do parking lots, buildings, air conditioners, etc. have a significant impact on thermometer readings?

Weren't all the thermometers used to make this graph on land? Doesn't that leave out the 75% of the earth's surface that is water?

If the warming trend were stark and obvious, the questions above would be less important. But one degree in a century? I can't feel one degree. I can't find two thermometers that agree that closely. The temperature regularly changes by 20 degrees or so every day where I live. On any given day at any given time, temperatures on the earth differ by more than 100 degrees F. What is signal and what is noise?


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