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Lennox
climber
just southwest of the center of the universe
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Sep 25, 2011 - 11:09pm PT
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Record cold or record wet?
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TGT
Social climber
So Cal
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Sep 25, 2011 - 11:13pm PT
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Cold in So Cal.
Really cold and dry in AZ
Wet and avg temps in N Cal
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dirtbag
climber
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Sep 25, 2011 - 11:18pm PT
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What a dumfuk.
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DrDeeg
Mountain climber
Mammoth Lakes, CA
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Sep 26, 2011 - 12:13am PT
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CC,
Not the case. The climate models include current knowledge about atmospheric properties, and the optical properties of gases and aerosols can be measured in the lab. Indeed aerosols (particles) cool, just not enough to offset CO2. Without them, the models overestimate the warming that CO2 would cause, but when included the models better match the observed warming (globally).
Here is a graph that gives an estimate of the forcing that has already occurred. The red (above the line) values are positive, and yes the Sun is there. Soot goes in both directions, because black carbon (coal, oil) is more absorptive than brown carbon. Note that the "snow" part of soot results from its deposition reducing the reflectivity (albedo) of snow. The other aerosols (mainly sulfur compounds) cool, so their forcing is negative. Their Indirect effect is through condensation nuclei for clouds. Land use change goes both ways. Decreasing evaporation forces positively, but cleared land is brighter and reflects more sunlight.
As for the temperature record, the graph below is the best estimate from a variety of sources. It is redrawn from a 2006 National Academy report Surface Temperature Reconstructions for the Last 2,000 Years (you can download a free PDF). You can ignore, if you wish, the colored lines on the right side of the graph, which are model projections under various future scenarios of CO2 concentration. All else is data. The wiggly black line shows the instrumental measurements starting around 1850. Previous measurements are proxies (tree rings, coral, etc) except the borehole measurements are directly measured temperatures. The last 1000 years were about 1.1 deg C cooler than the present, globally.
Regional variability will always be with us. Despite a warming trend, we will occasionally have cold winters, like last year on the east coast, and the incredibly hot summers, like a few months ago on the east coast too, are not surprising.
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Dr.Sprock
Boulder climber
I'm James Brown, Bi-atch!
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Sep 26, 2011 - 12:16am PT
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jesus controls everything,
set your thermostat to Jesus and relax.....
while we all burn up
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DrDeeg
Mountain climber
Mammoth Lakes, CA
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Sep 26, 2011 - 05:01pm PT
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Does 1 Watt per sq m matter? Is/was Earth in steady state?
In terms of the energy balance, an object's temperature moves toward a steady state, because it loses energy at a faster rate if its temperature increases. If the sun is out and you lay a black cloth on the ground, it will heat, but as it heats it emits more longwave radiation, so its temperature will stabilize.
How does this apply to Earth? Suppose its energy balance were out of whack by +1 Watt per sq m for 1,000 years. I have my students do a back-of-the-envelope calculation. The most likely place for the excess to go is the ocean, because energy exchange between it and the atmosphere is much faster than the land. In 1,000 years, the ocean mixes pretty well. The volume of water on Earth is about 1.4 billion cubic km, density of water is 1000 kg per cubic m, specific heat of water is 4185 Joules per deg per kg, and Earth's radius is 6371 km. Convert the 1 Watt per sq m to total Watts, and multiply the result by the number of seconds in 1,000 years. And divide this number by the kg of water x the specific heat.
The answer is about 3 degC. As the graph in my post above shows, we don't see that degree of variability in the 1,000 year record. Moreover, the density of water varies very slightly with temperature, so a 3 deg increase in temperature over 4000 m of water (the average depth of the ocean) would raise sea level by 2.5 m just from the expansion alone without considering melting of any ice.
So the evidence shows that Earth was nearly in steady state, with any long-term imbalance less than 1 Watt per sq m, for the 1,000 years before the Industrial Revolution. Currently, data from the CERES instrument on 3 satellites shows an imbalance over the last decade (that's the record we have of such detailed measurements) of about +2 Watts per sq m.
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corniss chopper
climber
breaking the speed of gravity
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Sep 26, 2011 - 05:21pm PT
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Rokjox - didn't they have to change over to a different type of cereal
crop that would grow in a colder northern Europe?
Now days it would not be a problem but back then
people did not have fast access to an alternate crop seed supply and lots of people died of starvation.
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DrDeeg
Mountain climber
Mammoth Lakes, CA
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Sep 26, 2011 - 06:56pm PT
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The Little Ice Age was really interesting -- wolves on the streets of Paris. My graph above (from Chapman & Davis) shows it, but the data show it was more pronounced in Europe than globally. Indeed, the existence of the Little Ice Age in the proxy data and in the climate models increases our confidence in the temperature reconstruction.
As noted in the 2006 National Academy Report Surface Temperature Reconstructions for the Past 2,000 Years:
“The instrumentally measured warming of about 0.6°C during the 20th century is also reflected in borehole temperature measurements, the retreat of glaciers, and other observational evidence, and can be simulated with climate models.
“Large-scale surface temperature reconstructions yield a generally consistent picture of temperature trends during the preceding millennium, including relatively warm conditions centered around A.D. 1000 (identified by some as the “Medieval Warm Period”) and a relatively cold period (or “Little Ice Age”) centered around 1700. The existence of a Little Ice Age from roughly 1500 to 1850 is supported by a wide variety of evidence including ice cores, tree rings, borehole temperatures, glacier length records, and historical documents. Evidence for regional warmth during medieval times can be found in a diverse but more limited set of records including ice cores, tree rings, marine sediments, and historical sources from Europe and Asia, but the exact timing and duration of warm periods may have varied from region to region, and the magnitude and geographic extent of the warmth are uncertain.
[My emphasis here] "It can be said with a high level of confidence that global mean surface temperature was higher during the last few decades of the 20th century than during any comparable period during the preceding four centuries. This statement is justified by the consistency of the evidence from a wide variety of geographically diverse proxies."
The point is that the data show that the previous 1,000 years was more stable than the last 100. The degree of variability during the Medieval Warm Period and the Little Ice Age indicate that Earth was nearer steady state then than it is now.
The reconstructions of the Little Ice Age from data, and its reproduction in models, increase our confidence about the magnitude and cause of the 20th-century warming. The CERES data showing that Earth currently absorbs about 2 W per sq m more than it emits give us reason to worry about climate, recognizing that measurements of this quality have only been available for a decade.
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TomCochrane
Trad climber
Santa Cruz Mountains and Monterey Bay
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Sep 28, 2011 - 12:49am PT
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corniss chopper
climber
breaking the speed of gravity
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the shape of things to come when you must use green appliances
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bookworm
Social climber
Falls Church, VA
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http://online.wsj.com/article/SB10001424052970203388804576612620828387968.html?mod=WSJ_Opinion_LEADTop
here are the highlights:
from the 2007 ipcc report: "most of the observed increase in global average temperatures since the mid-20th century is VERY LIKELY DUE to the observed increase in anthropogenic greenhouse gas emissions." (Emphasis in original.)
"And according to the International Energy Agency, the U.S. is now cutting carbon emissions faster than Europe, even though the European Union has instituted an elaborate carbon-trading/pricing scheme. Why? The U.S. is producing vast quantities of cheap natural gas from shale, which is displacing higher-carbon coal.
Meanwhile, China's emissions jumped by 123% over the past decade and now exceed those of the U.S. by more than two billion tons per year. Africa's carbon-dioxide emissions jumped by 30%, Asia's by 44%, and the Middle East's by a whopping 57%. Put another way, over the past decade, U.S. carbon dioxide emissions—about 6.1 billion tons per year—could have gone to zero and yet global emissions still would have gone up."
"The science is not settled, not by a long shot. Last month, scientists at CERN, the prestigious high-energy physics lab in Switzerland, reported that neutrinos might—repeat, might—travel faster than the speed of light. If serious scientists can question Einstein's theory of relativity, then there must be room for debate about the workings and complexities of the Earth's atmosphere.
Furthermore, even if we accept that carbon dioxide is bad, it's not clear exactly what we should do about it. In September, Tom Wigley of the National Center for Atmospheric Research in Boulder published a report that determined "switching from coal to natural gas would do little for global climate." Mr. Wigley found that the particulates put into the atmosphere by coal-fired power plants, "although detrimental to the environment, cool the planet by blocking incoming sunlight."
If Mr. Wigley's right, then using sources that emit no particulates, like nuclear and natural gas, will not make a major difference in averting near-term changes in the climate caused by carbon dioxide. But then—and here's the part that most media outlets failed to discuss when reporting on the Wigley study—widespread use of renewables such as wind and solar won't help much, either."
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Elcapinyoazz
Social climber
Joshua Tree
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hasmatt suit
This is the level of intellect you are dealing with in the denier crowd.
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Elcapinyoazz
Social climber
Joshua Tree
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You make no contentions. You ask easily answered questions, on a faulty premise that mercury in lighting is some new phenomenon. CFLs have considerably less mercury than the std tube fluorescent we've been using for 50 years. You have a silver dental filling? That's got at least 50 times more mercury than a CFL. Given the total lifetime energy savings of CFL vs incadescent, you introduce less mercury from CFL than an equivalent incadescent due to the excess energy use from coal fired plants, which introduce mercury from the coal.
Better, smarter trolls please.
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Mike Bolte
Trad climber
Planet Earth
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there is a thoughtful article comparing the controversies about climate change science with earlier controversies over the heliocentric model for the solar system and einstein's general relativity.
http://physicstoday.org/resource/1/phtoad/v64/i10/p39_s1
Here is a little excerpt:
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"When observation, by Arthur Eddington and others, of a rare solar eclipse in 1919 confirmed the bending of light, it was widely hailed and turned Einstein into a celebrity. Elated, he was finally satisfied that his theory was verified. But the following year he wrote to his mathematician collaborator Marcel Grossmann:
This world is a strange madhouse. Currently, every coachman and every waiter is debating whether relativity theory is correct. Belief in this matter depends on political party affiliation.
Instead of quelling the debate, the confirmation of the theory and acclaim for its author had sparked an organized opposition dedicated to discrediting both theory and author. "
Remarkably similar to today's debate about climate change!
By the way, Eddington's 1919 observations of the deflection of starlight by the Sun were shown to have errors that were much too large to verify or refute the predictions of general relativity. It took several years of refining the techniques to finally get good enough data to establish GR's predictions to be closer to the truth than Newtonian predictions.
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dirtbag
climber
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You guys are being trolled by the bw bs misinformation machine.
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dirtbag
climber
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Well I'm warming up! Thanks man!
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