News The Scientific Consensus on Climate Change

[Skyhunter]

Sorry if it seems overly aggressive or argumentative, Skyhunter and I were right in the middle of heated debate I suppose

Oh it wasn't heated...just globally warmed.



On the serious side.

Most of the warming did not occur pre 1940, as this http://www.grida.no/climate/ipcc_tar/wg1/figspm-1.htm illustrates.

[edit] The graph above does not include the last 6 years which have shown an even greater increase n temperature. [/edit]

 

[Bystander]

1860-1920 lumps, rises, falls, no obvious net change; 1920-1940 0.5 increase; 1945-1970 cools a couple tenths; 1970-2000 increase of 0.4-0.5.

Care to give us short sketches of economic activity, global political activity, station locations, and measurement methods for those periods?

 

[Skyhunter]

1860-1920 lumps, rises, falls, no obvious net change; 1920-1940 0.5 increase; 1945-1970 cools a couple tenths; 1970-2000 increase of 0.4-0.5.

Care to give us short sketches of economic activity, global political activity, station locations, and measurement methods for those periods?

I didn't produce the data. It is all part of the IPCC report. Not even Mr. Lindzen disagrees with the science behind the report, just the predicted consequences. Until I see compelling evidence to the contrary I will go with the data that the top climate scientists in the world have compiled.

[edit] Looking at the second graph of the past 1000 years is even more telling. The warming coincides with widespread industrialization.

Nevertheless the rate and duration of warming of the 20th century has been much greater than in any of the previous nine centuries. Similarly, it is likely7 that the 1990s have been the warmest decade and 1998 the warmest year of the millennium.

And 2005 was warmer still.

[/edit]

 

[Bystander]

... go with the data that the top climate scientists in the world have compiled.

From http://www.nws.noaa.gov/pa/history/timeline.php

1933: A science advisory group apprizes President Franklin D. Roosevelt that the work of the volunteer Cooperative Weather observer network is one of the most extraordinary services ever developed, netting the public more per dollar expended than any other government service in the world. By 1990 the 25 mile radius network encompasses nearly 10,000 stations.
​

Examining the map from http://en.wikipedia.org/wiki/Mean_center_of_U.S._population the population center is near Columbus, Ind. in 1900 http://www.wunderground.com/NORMS/DisplayNORMS.asp?AirportCode=KBAK&SafeCityName=KBAK&StateCode=IN&Units=none ; Bloomington in 1930 http://www.wunderground.com/NORMS/DisplayNORMS.asp?AirportCode=KBMG&SafeCityName=KBMG&StateCode=IN&Units=none ; and Rolla, Mo. in 2000 http://www.wunderground.com/NORMS/DisplayNORMS.asp?AirportCode=KVIH&SafeCityName=KVIH&StateCode=MO&Units=none

"Volunteer observers" may, or may not, be distributed uniformly throughout the general population. Are they "New Soviet Citizens" loyal to their duties, tending fixed "weather outposts" for the "good of the proletariat?" Or, do they pack up and move with the job market like the rest of us?

Or, more bluntly, has the center of "mass" of the "global thermometer" moved to warmer climes?

The mid-June to August gap for Columbus is one of today's "features" for whatever's going on with the net --- it's more or less a set of equally ragged interpolations between the pairs of points defining the gaps in each record.

 

[Skyhunter]

Or, more bluntly, has the center of "mass" of the "global thermometer" moved to warmer climes?

When a volunteer weather and temperature observer moves from Columbus Indiana to Bloomington Indiana, don't you think he/she will report their new location as well as the temperature?

 

[Bystander]

http://www.ncdc.noaa.gov/img/climate/research/ushcn/ts.ushcn_anom25_diffs_pg.gif

A "description" of these six "corrections" (don't want to call them out and out fudge factors just yet) is included with the document from which the link to the plot of the "corrections" is taken,

http://www.ncdc.noaa.gov/oa/climate/research/ushcn/ushcn.html#KDK88 .

Haven't been to the library yet to hunt down Karl, '86 and Karl '88; all should feel free to add summaries of these two papers (the two large "corrections" applied to temperature data in this case).

 

[edward]

Any data older than three or four years can be tossed out of the global warming equation. It doesn't really matter what the temperature of the Earth was in 1940-1960-or1980.

More recent studies are the gold standard now. The melting of the permafrost in Siberia alone will greatly affect the rate of global warming by increasing the amounts of CO2 and Methane in the atmosphere. This fact wasn't even considered relevant until recently.

The researchers found that what was until recently a barren expanse of frozen peat is turning into a broken landscape of mud and lakes, some more than a kilometre across.

Dr Kirpotin told the magazine the situation was an "ecological landslide that is probably irreversible and is undoubtedly connected to climatic warming". He added that the thaw had probably begun in the past three or four years

http://www.guardian.co.uk/climatechange/story/0,12374,1546824,00.html

Human activity does not have to be the total cause. Anthropogenic warming only had to be the catalyst that started the natural processes that are beginning.

 

[Skyhunter]

Why are you trying to confuse the issue?

Here is the final graph from the same website. Minus the raw data.

http://www.ncdc.noaa.gov/img/climate/research/ushcn/ts.ushcn_anom25_diffs_urb-raw_pg.gif

Looks very similar to the one I linked in my previous post.

 

[Bystander]

That's called "clarification" of the issue; we're interested in discovering the origin of the temperature trend --- right now it's not based on the data, but on "corrections" to the data. Next question (already stated) is, "What are Karl's "corrections" based upon?"

 

[Skyhunter]

That's called "clarification" of the issue; we're interested in discovering the origin of the temperature trend --- right now it's not based on the data, but on "corrections" to the data. Next question (already stated) is, "What are Karl's "corrections" based upon?"

My apologies, I misunderstood.

This graph has the raw data.

http://www.ncdc.noaa.gov/img/climate/research/ushcn/rawurban3.5_pg.gif

Karl's adjustments are explained in the Quality Control, Homogeneity Testing, and Adjustment Procedures section on the same NOAA website. For the exact methodology and procedures I guess we will have to read their publications.

Easterling, D.R., and T.C. Peterson, 1995: A new method of detecting undocumented discontinuities in climatological time series, Int. J. of Climatol., 15, 369-377.
Karl, T.R., C.N. Williams, Jr., P.J. Young, and W.M. Wendland, 1986: A model to estimate the time of observation bias associated with monthly mean maximum, minimum, and mean temperature for the United States, J. Climate Appl. Meteor., 25, 145-160.

Karl, T.R., and C.W. Williams, Jr., 1987: An approach to adjusting climatological time series for discontinuous inhomogeneities, J. Climate Appl. Meteor., 26, 1744-1763.

Karl, T.R., H.F. Diaz, and G. Kukla, 1988: Urbanization: its detection and effect in the United States climate record, J. Climate, 1, 1099-1123.

Karl, T.R., C.N. Williams, Jr., F.T. Quinlan, and T.A. Boden, 1990: United States Historical Climatology Network (HCN) Serial Temperature and Precipitation Data, Environmental Science Division, Publication No. 3404, Carbon Dioxide Information and Analysis Center, Oak Ridge National Laboratory, Oak Ridge, TN, 389 pp.

Peterson, T.C., and D.R. Easterling, 1994: Creation of homogeneous composite climatological reference series, Int. J. Climatol., 14, 671-680.

Quayle, R.G., D.R. Easterling, T.R. Karl, and P.Y. Hughes, 1991: Effects of recent thermometer changes in the cooperative station network, Bull. Am. Meteorol. Soc., 72, 1718-1724.

[edit] Maybe this thread is ready to be moved back into Earth Sciences Forum. [/edit]

 

[SOS2008]

We know there has been a history of dramatic climate changes on the Earth. This may well be cyclical most of the time, but some times it is due to cataclysmic events, such as an asteroid impact. The current climate changes also may be cyclical. However, the accelerated rate of change remains suspect. How much of an effect human activity is having on the rate of change may not need to be that large to "push the envelope" as it were.

Regardless of cause, ultimately the change is not likely to be a positive one. We must look at all the variables (e.g., deforestation) to slow or reverse the trend. To argue against this is very irresponsible and a great disservice to all. Including other species that we share this planet with:

"Is climate turning polar bears into cannibals?
U.S. and Canadian scientists report kills linked to shrinking ice"
http://msnbc.msn.com/id/13288936/?GT1=8211

 

[Bystander]

(snip)This graph has the raw data.(snip)Karl's adjustments are explained in the Quality Control, Homogeneity Testing, and Adjustment Procedures section ...(snip)

Thank you for going through the link.

[edit] Maybe this thread is ready to be moved back into Earth Sciences Forum. [/edit]

Prolly, it ain't --- still getting "political" positions on the question --- and, those do NOT belong in Earth Science.

Back to USHCN, and raw data plus six corrections; let's just play with the "Urban Heat Island" (UHI) for the moment. The argument is that urbanization over the past century has affected temperatures recorded by stations around which urban centers have built in, increasing them over time. Is that your understanding?

Further, since we're interested in the "temperature signal" resulting from climate change, it's necessary to apply a "correction" if the UHI effect can be quantified (Karl '88)?

"Karl '88" uses satellite data to quantify the UHI from daytime and nighttime IR data over urban and rural areas within same, or similar, regions, microclimates, climate zones, whatever. From this, Karl, USHCN, or others, arrive at a UHI effect which increases from near zero at the beginning of the century to 0.3 degree at the end of the century.

Then, since the raw data includes the UHI effect, and the climate signal is the information of interest, the time dependent correction is ADDED ??! to the raw data?

Understand that I've concluded nothing to this point; description of "adjustment procedures" on the USHCN page is unacceptably vague from the standpoint of publication in the scientific literature, and translation from the "turnip-speak" of internet pages for public consumption to some idea of what was actually done during data reduction is a bit of a slow and painful process --- that's what libraries are for --- Karl is on the list for the next trip. The sciences are full of "sign conventions," European vs. American redox potentials, q+w vs. q-w in thermo --- the climate crowd may have borrowed some sort of "debit-credit" system from bookkeepers, and I'm just tripping over their definition of "correction."

 

[Skyhunter]

Thank you for going through the link.

thank you for posting it.

Back to USHCN, and raw data plus six corrections; let's just play with the "Urban Heat Island" (UHI) for the moment. The argument is that urbanization over the past century has affected temperatures recorded by stations around which urban centers have built in, increasing them over time. Is that your understanding?

Yes it is. I find the science fascinating and would like to hear of your trip through to the library.

Back to the politics.

Referring back to Edwards point about data from the last few years only, being relevant to what is happening now is poignant. The oceans are warming rapidly and as anyone who lives next to a coast can attest, the water warms and cools much slower than the land and air.

From the link Edward posted.

In an interview with the BBC Barnett noted that the world's oceans cover around 71 percent of the Earth's surface, and that what happens in them therefore has significant consequences on the world's weather and climate. The study used advanced computer models of climate "to calculate human-produced warming over the last 40 years in the world's oceans," said Scripps' bulletin. "In all of the ocean basins, the warming signal found in the upper 700 meters predicted by the models corresponded to the measurements obtained at sea with confidence exceeding 95 percent. The correspondence was especially strong in the upper 500 meters of the water column."

The bulletin noted that it is this "high degree of visual agreement and statistical significance that leads Barnett to conclude that the warming is the product of human influence. Efforts to explain the ocean changes through naturally occurring variations in the climate or external forces- such as solar or volcanic factors--did not come close to reproducing the observed warming."

95% is the threshold of statistical significance. If the warming is real, and the ocean temperature in my mind is a certain indicator of global warming, and that warming is significantly due to human activity, then that is a political problem that should be dealt with, not denied because there is a 5% chance, or 10%, 20%, even 50% chance it could be something else.

To argue that there is nothing we can do because soon we won't be the major contributor is shirking the responsibility this country has to lead the world through innovation and example.

America has the resources, we should be taking the lead not sitting on the sideline in denial.

 

[Bystander]

Quote:
(snip)Back to the politics.

Referring back to Edwards point about data from the last few years only, being relevant to what is happening now is poignant. The oceans are warming rapidly and as anyone who lives next to a coast can attest, the water warms and cools much slower than the land and air.

From the link Edward posted.

Quote:
In an interview with the BBC Barnett noted that the world's oceans cover around 71 percent of the Earth's surface, and that what happens in them therefore has significant consequences on the world's weather and climate. The study used advanced computer models of climate "to calculate human-produced warming over the last 40 years in the world's oceans," said Scripps' bulletin. "In all of the ocean basins, the warming signal found in the upper 700 meters predicted by the models corresponded to the measurements obtained at sea with confidence exceeding 95 percent. The correspondence was especially strong in the upper 500 meters of the water column."

The bulletin noted that it is this "high degree of visual agreement and statistical significance that leads Barnett to conclude that the warming is the product of human influence. Efforts to explain the ocean changes through naturally occurring variations in the climate or external forces- such as solar or volcanic factors--did not come close to reproducing the observed warming."

The Guardian links to Scripps and AAAS didn't go anywhere but to "treasure hunting" generic sites --- so, let's see what we can come up with for "predicted signals" (the LLNL model) and field data that are going to confirm the model and AGHGW. Little snooping gives depth-T profiles for vicinity of Canary Islands ( http://www.atlantic-cable.com/Cables/1970TRANSCAN/ ), and the summer-winter variation at 700 m is 3 K. That's almost entirely due to vertical mixing processes; summer-winter insolation rate difference is around 60W/m², and that'll account for maybe 1-2%. Vertical temperature gradient is 15-20 mK/m. Depth control on towed or stationary measurements (currents dragging instrument cables sideways) isn't going to be much better than 10 m; 0.15 to 0.20 K is going to be the smallest difference I can see and call significant. Year to year variations in the summer-winter difference? Due to decadal variations in average surface wind speeds? Drifting of gyres? "Whipping" of currents (Gulf Stream, Humboldt, Japanese, you name it)? Order of 1 K --- maybe more. How densely populated is the field data to which the model is compared? No more densely than any other oceanographic data type --- translates as "sparse." The "model predictions?" Gonna be based on a "greenhouse" decrease in surface heat loss of 1-2 W/m², over 40 a, is around 0.5 K at 700 m --- not really out of the background noise level.

95% is the threshold of statistical significance. If the warming is real, and the ocean temperature in my mind is a certain indicator of global warming, and that warming is significantly due to human activity, then that is a political problem that should be dealt with, not denied because there is a 5% chance, or 10%, 20%, even 50% chance it could be something else.

To argue that there is nothing we can do because soon we won't be the major contributor is shirking the responsibility this country has to lead the world through innovation and example.

America has the resources, we should be taking the lead not sitting on the sideline in denial.

"Tipping point" is one phrase to "tip" you off to the fact that you're being handed a line. "Smoking gun" is another. "Efforts to explain the _______ through naturally occurring variations in the climate or external forces- such as solar or volcanic factors--did not come close to reproducing the observed warming," is yet another --- it translates as, "We are either too incompetent to recognize the factors affecting the system we're examining, or we're too damned lazy to do so, and would rather pull the wool over peoples' eyes if they're too lazy to call us on it."

 

[SOS2008]

While the climate system is very complex and difficult to model precisely, the Intergovernmental Panel on Climate Change (IPCC) is increasingly certain that humans have a discernible influence on the global climate. Confirmation of the measured warming trend is substantiated by the rise in sea level of between four and 10 inches that has occurred since 1900 and the decrease in the average snow cover and glacial ice worldwide. Unseasonable weather phenomena are becoming commonplace and intensities appear to be increasing. A continued increase in greenhouse gas emissions, and the associated temperature rise, is likely to accelerate the rate of climate change, producing further impacts.

http://www.climatechange.ca.gov/background/faqs.html

Increased emissions of greenhouse gases have led to changes in precipitation, ocean salinity, CO2 absorption by the sea, water temperature, winds and pH levels. This is having a demonstrated impact on marine ecology and fisheries. The Inter-Governmental Panel on Climate Change (IPCC) reports that marine-disease and algal species are affected by these factors and that “in recent decades there has been an increase in reports of diseases affecting coral reefs and sea grasses, particularly in the Caribbean and temperate zones” (14)

Future climate change scenarios and models vary widely, but all agree that marine ecology will change significantly and quickly.

The IPCC is a UN-funded group of 2,500 leading climate scientists. Their fifth technical report found that coral reef systems have already begun to be affected by climate change, and refers to flow-on effects – being recorded now – that affect temperate zone fisheries too. In Australia, for example, it is predicted that temperate endemic species will be more severely affected than tropical (AGO, 2003).

A report commissioned by WWF (Are we putting our fish in hot water?) found that increased ocean temperatures means less food, less offspring and even less oxygen for marine and freshwater fish populations.

Global warming can cause fish populations to migrate: fish stocks in the North Sea have been forced to move scores of miles north to cooler waters, according to a study by climate change scientists

One scientist that took part in the North Sea study said: "What's striking is people tend to think of climate change as something that's going to affect us in the future, whereas more and more we're seeing signs that these changes are already happening and are going to continue."

via a link on this site: http://risingtide.org.au/node/60

I don't have time to google for more sources at this moment. But why argue about modeling methods to predict the future when there are variables such as rising water levels, shrinking glaciers/ice, etc. that can be clearly measured right NOW?

 

[Bystander]

http://www.climatechange.ca.gov/background/faqs.html

via a link on this site: http://risingtide.org.au/node/60

I don't have time to google for more sources at this moment. But why argue about modeling methods to predict the future when there are variables such as rising water levels, shrinking glaciers/ice, etc. that can be clearly measured right NOW?

From the IPCC: http://www.grida.no/climate/ipcc_tar/wg1/420.htm#tab118 ; the table is the only thing we're interested in at the moment, IPCC estimates of terrestrial (continental --- excluding Antarctica and Greenland) contributions to mean sea level over the past century as annual rates for assorted terms in the global mass balance for water. Dept. of Interior's figures for U. S. are that the nation has pumped 1000 km³/a for the last 20-25a. Global pumping is around 3000. Hydrologists estimate the average recharge time for aquifers exposed to normal rainfall (whatever that is) to be 3ka. Wells tapping aquifers in the U. S. exhibit water level drops of hundreds of feet over the century. That's right, this is P&WA --- I've got to do the arithmetic for people --- 100,000 -180,000 km³ pumped from aquifers globally over past century. IPCC says 90% went right back in --- a bit of a disagreement with hydrologists, conservationists, and well water levels, but we'll let that slide for the mo'. For the math impaired, a 10 cm sea level rise is a change in ocean volume of 35,000 km³; using IPCC's 90% recharge, that's 0.3-0.5 mm/a over the century. Using hydrologists' recharge rates, "... aquifers are being pumped at many times the recharge rate," we're into the field of "adjectival quantification," or, more colloquially, "hand-waving." What does "many times" equal numerically? Probably more than IPCC's 1.1 --- 1.5? That's a 70% recharge rate, implies aquifers would recover in decades rather than millennia (the 3000a recharge figure), puts 30-54,000km³ into the oceans, pretty much in line with the 10-20 cm rises for the 20th century. What's IPCC missed? Aquifers were full "to the brim" at the end of the last ice age --- melting at the ice-substrate interface (ground) had been going on at the rate of 0.1 - 1.0 mm/a for a couple hundred thousand years, and that crustal heat flow meltwater had no place to go but into the ground. Ice age ends, and the aquifers are back to precipitation recharge --- they "relax" to some new steady state water level that is a function of recharge rate, porosity (capacity), and permeability (controls rate of lateral movement in response to whatever pressure head is present). What's the time constant for that relaxation? Archaeologists have been locating coastal settlements 10 m below current sea level, ages around 6ka, at the rate of one every 2-4 years. Sea level stopped rising at the time of the Renaissance? The industrial age? Don't think so --- there's going to be a natural background rate that's on the order of 3-30 cm a century just from aquifer relaxation. Whatta we got? 13-50 cm rise for the 20th century without having to melt anything --- an overstatement of GW as THE driver for sea level change.

What's next? Melting tundra? Accelerating glaciers? Atmospheric CO₂ levels?

Tundra? Okay --- this is a homework assignment: calculate the change in heat transport northward through the Bering Strait due only to a 10 cm increase in sea level; report the result in mid-summer insolation days at the latitude of the Arctic Circle for 10,000 km² and 100,000 km² areas.

Glaciers? Extra credit: write an expression for flow at any point of a circular ice sheet of fixed radius sitting on a perfectly flat surface bounded by a drop-off, or sink, being replenished at a uniform rate over its areal extent by snowfall; use cylindrical coordinates, with origin at the center of the ice sheet.

CO₂? This is an "n"-parter: compare annual fossil fuel emissions to annual exchange between atmosphere and biosphere (terrestrial and marine); compare equilibrium solubility in oceans with total carbon content of oceans; estimate a "sequestration" rate for the marine biosphere from the marine carbon content and the circulation time for the oceans; compare this to the annual catch by commercial fisheries; compare the "sequestration" rate to marine productivity; compare the sequestration rate to historical estimates of "commercial" fish stocks.

 

[edward]

No homework assignments for me thanks. Your are basing too much on sea levels transferring heat north?? The sun will do that as snow and ice melt and the bare dark exposed Earth absorbs much more heat than the reflective snow or ice. Plus that bare unfrozen ground only needs a fraction of the amount of the heat that was needed to thaw it to warm it significantly.

This is already happening in several vast areas. That is why the permafrost is melting. The Siberian permafrost alone will nearly double the amount of CO2 presently in the atmosphere. see the link.

People are too hung up on old data. It is the information which is new that will be the big surprise, especially in determining the rate of accelerated change in the global warming issue.

 

[SOS2008]

<snip>

Skipping past the unnecessary insults... The growing human population has increased demand for potable water, which is only a small percentage of the total amount of water on the Earth. So if this water is being pumped faster to meet growing needs and resulting in lower aquifer levels, that would be no surprise to anyone. If anything, it is only an additional concern.

Global warming causes hot, arid regions to become hotter and more arid, and wet regions to become wetter. When there is rain, it becomes more torrential and erosive. That means potable water will simply become less available in more areas of the world. It's certainly a big concern here in the Southwest, for example:

"Due to last summer's drought conditions, the soil is very dry, deeper ground water is reduced and water storage reservoirs are well below average. Therefore, a significant portion of the melt from this year's snowpack will be absorbed into the ground and into ground water before beginning to fill depleted reservoirs," said Pielke. "It will take more than average snowpack to produce average runoff into reservoirs, and much more than an average snowpack to fill the depleted reservoirs to average levels."

Other climate and weather experts agree. According to NOAA's U.S. Drought Outlook, recent storms greatly improved water supply prospects in Colorado's basins. However, the report states that the odds for significant change in the status of the long-term drought decline as the snow season wanes, and their forecast is for limited improvement.

http://ccc.atmos.colostate.edu/newsapr1.php

In addition to water shortages, there are increasing wildfires that affect the atmosphere. For how long does this trend need to continue before the consequences are serious? What can be done to reverse it? I don't understand why anyone would not want to address such questions.

 

[Skyhunter]

According to the study cited in this article the rate of rise in sea level is accelerating.

In an attempt to reduce the scale of uncertainty in this projection, the Australian researchers have analysed tidal records dating back to 1870.

The data was obtained from locations throughout the globe, although the number of tidal gauges increased and their locations changed over the 130-year period.

These records show that the sea level has risen, and suggest that the rate of rise is increasing.

Over the entire period from 1870 the average rate of rise was 1.44mm per year.

Over the 20th Century it averaged 1.7mm per year; while the figure for the period since 1950 is 1.75mm per year.

Although climate models predict that sea level rise should have accelerated, the scientists behind this study say they are the first to verify the trend using historical data.

http://news.bbc.co.uk/1/hi/sci/tech/4651876.stm

During my reading about sea levels I read that approximately 6% of total water influx to the oceans and seas comes from direct groundwater discharge.

Change in climate means there is a change in precipitation and evaporation rates, constituents of the hydrologic cycle, which affect surface runoff, and groundwater and ocean levels (Klige, 1990; Zester and Loaiciga, 1993; Loaiciga et al., 1996).

If the rate of rise is increasing, is it due only to the pumping of groundwater?

 

[Bystander]

No homework assignments for me thanks. Your are basing too much on sea levels transferring heat north??]/QUOTE]

Nope. That was the point of the homework --- you inform yourself, we don't have to go through this drill.

Atlantic conveyor moves heat northward to the tune of 10¹⁵W; current through the Bering Strait moves heat northward into the Chukchi Sea at 4x10¹³W. Atlantic heat keeps Europe warm enough to be inhabitable. The heat transferred to the Chukchi from N. Pac. is then transferred to Siberia by the southwesterly surface winds (driven by the north polar atmospheric circulation cell and coriolis effects). Average depth of the Bering Strait is around 50m; sea level rise over the past century is 10-20 cm; flow increase is 0.2-0.4% --- water temperatures in N. Pac. haven't changed that much, so heat flow has increased by same amount, 0.2-0.4W/m² over the area of the Chukchi. Average insolation above the Arctic Circle? 15-20W/m². Increase "expected" due to "GHW?" Around 1%, 0.2W/m². Sea level rise is real. The north polar atmospheric convection is real. GHW should affect the entire Arctic Circle uniformly, not in spots.

(snip)
People are too hung up on old data.

That was Aristotle's complaint, wasn't it? You know --- the guy who spontaneously created mice from piles of old clothes.

"Climate" isn't too well defined; the closest thing I've seen to a decent definition as far as taking a scientific approach is that, "Climate is an average temperature." I'd add, "and other variables describing weather, wind speed, direction, humidity, rainfall," you get the picture; and I'd specify the time period over which these variables are to be averaged, 200 year sliding average, global (over all time of observation); something along the lines of tide gauging --- you set up your tide station, you run it for 26 years (lets you "look" at the precession of the lunar orbital axis), then you start reporting 26 year sliding averages of "mean sea level" for 13 years earlier. Lunar precession affects weather patterns; solar sunspot cycles (9-11 years) also affect weather patterns; we're looking at a minimum time span for a "climatic sliding average" of 200-300 years to see all combinations of lunar and solar effects on weather before we can start reporting 100-150 year old climate data.

It is the information which is new that will be the big surprise,

Computer models? No surprise --- GIGO, couple truckloads of lousy meteorological data (perfectly serviceable for its original purpose, weather prediction), plus a couple dozen flaky assumptions, push the button, and out pop a couple truckloads of garbage plus a couple dozen flaky assumptions all dressed up as the "latest in climate models."

especially in determining the rate of accelerated change in the global warming issue.

 

[Astronuc]

I am not sure about the 'scientific consensus'. There are scientists who support GW, and those who disagree. Clearly politics is involved. For example, Exxon-Mobil sponsors some scientific groups who question GW, so one has to question the integrity of those groups.

Meanwhile,

http://video.google.com/videoplay?docid=3412657607654281729&q=tvshow%3ACharlie_Rose (availability might be limited timewise)

An hour with former Vice President Al Gore. He discusses his new film, 'An Inconvenient Truth' and the science and politics surrounding global warming.

Visit www.climatecrisis.net (but turn the sound down - broadband may be necessary due to the graphics and audio).

More to the point -

http://www.climatecrisis.net/thescience/

http://www.climatecrisis.net/takeaction/

 

[Ivan Seeking]

There are scientists who support GW

I recently saw a bumper sticker on an old, smokey Suburban, that said:
I support global warming.

 

[Astronuc]

I recently saw a bumper sticker on an old, smokey Suburban, that said:
I support global warming.

Let me rephrase my comment then, "There are scientists who support the idea that human activity (vis-a-vis production of greenhouse gases) is primarily responsible for GW (i.e. increase in atmospheric and oceanic enthalpy), and those who believe human activity does not.

 

[edward]

No homework assignments for me thanks. Your are basing too much on sea levels transferring heat north??

Nope. That was the point of the homework --- you inform yourself, we don't have to go through this drill.

Below is your statement that I was referring to. It seems to be linking heat transferred north to sea levels. That is why I included the ?? in my post.

Tundra? Okay --- this is a homework assignment: calculate the change in heat transport northward through the Bering Strait due only to a 10 cm increase in sea level; report the result in mid-summer insolation days at the latitude of the Arctic Circle for 10,000 km2 and 100,000 km2 areas.

I AM NOT YOUR STUDENT so please refrain from this type of ulterior motive posting to sling insults, it is useless.

Atlantic conveyor moves heat northward to the tune of 10¹⁵W; current through the Bering Strait moves heat northward into the Chukchi Sea at 4x10¹³W. Atlantic heat keeps Europe warm enough to be inhabitable. The heat transferred to the Chukchi from N. Pac. is then transferred to Siberia by the southwesterly surface winds (driven by the north polar atmospheric circulation cell and coriolis effects). Average depth of the Bering Strait is around 50m; sea level rise over the past century is 10-20 cm

Very true, but as I am sure you are aware, the natural systems by which the oceans tranfer heat north are very fragile. The melting of the northern ice, and it is melting, will inevitably dilute the salinity of the northern ocean waters. This has been discussed in other threads. We may end up having Northern Europe freeze while the rest of the Earth is still warming.

"Climate" isn't too well defined; the closest thing I've seen to a decent definition as far as taking a scientific approach is that, "Climate is an average temperature." I'd add, "and other variables describing weather, wind speed, direction, humidity, rainfall," you get the picture; and I'd specify the time period over which these variables are to be averaged, 200 year sliding average, global (over all time of observation); something along the lines of tide gauging --- you set up your tide station, you run it for 26 years (lets you "look" at the precession of the lunar orbital axis), then you start reporting 26 year sliding averages of "mean sea level" for 13 years earlier. Lunar precession affects weather patterns; solar sunspot cycles (9-11 years) also affect weather patterns; we're looking at a minimum time span for a "climatic sliding average" of 200-300 years to see all combinations of lunar and solar effects on weather before we can start reporting 100-150 year old climate data.

Thank you sir. You have summed up exactly why the use of extravagant old data is futile in determining what is happening right now because GW is happenning right now.

The Scripps studies which were backed up and supported by Livermore were enough to convince many people, with the possible exception of certain politicians who still live on a flat earth. Add the more recent melting of the permafrost data to that and we a big problem.

Here is an intersting link from the Woods Hole Institute.
http://www.whoi.edu/institutes/occi/viewArticle.do?id=9206

 

[Skyhunter]

I came across this in my studies.

[The following was posted by Dr. Jeff Masters (Ph.D. in air pollution meteorology from U. Michigan), and a co-founder of Weather Underground]

[see http://www.wunderground.com/blog/JeffMasters/ comment.html?entrynum=385&tstamp=200606]

I've had several people ask about the study Al Gore talked about in his movie, which found found no scientific papers disputing the reality of human-caused climate change over the past ten years. Well, to be sure, there have been a few papers disputing the reality of human-caused climate change published in the past ten years, but they didn't happen to have the key words "global climate change" included in their citations. The study Gore cites was published in December 2004 in Science magazine by Naomi Oreskes, a professor at UC San Diego. The article examined peer-reviewed studies in the world's major scientific journals between 1993 and 2003 containing the phrase "global climate change" as keywords. Oreskes found that 75% of the 928 articles with those key words in their citations agreed with the consensus position stated by the UN's panel on climate change, that the observed global warming over the past 50 years has been caused in part by human activity. The other 25% of the papers took no position, and none of the papers disagreed with the consensus view. While the study is not a perfect measure of the scientific uncertainty in the published literature, the study does show that an overwhelming majority of published scientific research supports the idea that human activity is significantly modifying Earth's climate.

As Gore noted in his movie, the situation is quite different in the media, where about half of the stories in the study he cited cast doubt on the reality of human-caused climate change. The media are fond of trying to report both sides of an issue, so in the name of journalistic fairness, the public is receiving a highly skewed view of the scientific debate on climate change. In many cases, the opposing views presented by the media are from fossil fuel industry-funded "think tanks" that routinely put out distorted and misleading science intended to confuse the public.

I've collected a list of climate change position papers put out by the major governmental scientific institutes of the world that deal with the atmosphere, ocean, and climate. All of these organizations agree that significant human-caused climate change is occurring:

United Nations IPCC American Meteorological Society NOAA U.S. National Academy of Sciences NASA EPA American Geophysical Union National Center for Atmospheric Research Royal Society of the United Kingdom Canadian Meteorological and Oceanographic Society

Science Council of Japan, Russian Academy of Science, Brazilian Academy of Sciences, Royal Society of Canada, Chinese Academy of Sciences, French Academy of Sciences, German Academy of Natural Scientists Leopoldina, Indian National Science Academy, Accademia Nazionale dei Lincei (Italy), Royal Society (UK)

Australian Academy of Sciences, Royal Flemish Academy of Belgium for Sciences and the Arts, Brazilian Academy of Sciences, Royal Society of Canada, Caribbean Academy of Sciences, Chinese Academy of Sciences, French Academy of Sciences, German Academy of Natural Scientists Leopoldina, Indian National Science Academy, Indonesian Academy of Sciences, Royal Irish Academy, Accademia Nazionale dei Lincei (Italy), Academy of Sciences Malaysia, Academy Council of the Royal Society of New Zealand, Royal Swedish Academy of Sciences, and Royal Society (UK)

If anyone can find examples of governmental scientific organizations that deny the consensus position, I'd be happy to make a second list of links. Saudi Arabia and Kuwait have long been hostile to international climate change negotiations, so their scientific organizations may well have official positions opposing the consensus. However, the Saudis are apparently changing their stance, as announced in May 2006 at a U.N. sponsored meeting in Germany. "I believe the petroleum industry should actively engage in policy debate on climate change as well as play an active role in developing and implementing carbon management technologies to meet future challenges," said the president of the Saudi state-run oil industry giant, Aramco. In 2005, both Saudi Arabia and Kuwait signed and ratified the Kyoto Protocol to limit greenhouse gases. The Protocol does not call on them to reduce their emissions.

In summary, there is an overwhelming level of scientific consensus on human-caused climate change. Those who defend the contrary view are fond of pointing out that we shouldn't stifle their opposing point of view, since heroes like Galileo with his sun-centered solar system view and Wegener with his continental drift theory both challenged the overwhelming scientific consensus of their day and were proved to be correct. That is true. However, Galileo and Wegener did not have the public relations staff of multi-billion dollar companies helping them promote their contrary views. I'm not too worried about the contrarian view of human-caused climate change being stifled, and contrarians are encouraged to publish in the peer-reviewed scientific literature. I would like to see the media sharply reduce their coverage of the contrary views of such think tanks as the Competitive Enterprise Institute, George C. Marshall Foundation, and scientists such as S. Fred Singer of the SEPP. Let's focus on the published scientific literature.

Jeff Masters

Are there any governmental scientific institutions denying AGW?

[edit] Go to his web page for links to the position papers of the above mentioned science institutes. [/edit]

 

[Bystander]

I am not sure about the 'scientific consensus'. There are scientists who support GW, and those who disagree. Clearly politics is involved. For example, Exxon-Mobil sponsors some scientific groups who question GW, so one has to question the integrity of those groups.
(snip)

--- and, GE, Westinghouse, Bechtel, Brown & Root (the nuclear power club), the insurance industry (anticipatory rate hikes to cover increased casualty losses), and, the biggie, the Chicago Board of Trade --- got to be hundreds of billions a year in CO₂ futures. There's plenty of money on both sides, and BIIGGG stakes.

_______________________________________________________

I recently saw a bumper sticker on an old, smokey Suburban, that said:
I support global warming.

https://www.physicsforums.com/showthread.php?t=114123

________________________________________________________

Below is your statement that I was referring to. It seems to be linking heat transferred north to sea levels. That is why I included the ?? in my post.

Increased sea level implies increased mass transport through the Bering Strait implies increased heat transport. If you're talking about melting in the Arctic Circle region you are familiar with the geography?

"Climate" isn't too well defined; (snip); we're looking at a minimum time span for a "climatic sliding average" of 200-300 years to see all combinations of lunar and solar effects on weather before we can start reporting 100-150 year old climate data.

You have summed up exactly why the use of extravagant old data is futile in determining what is happening right now because GW is happenning right now.

I'm paraphrasing because I'm not certain I understand what you're saying here: you are asserting that you can, from a single observation, with no history of the system, determine the dynamic state of the system and predict its future behavior? Don't wanta go putting words into your fingers.

 

[Skyhunter]

Aramco has reversed it's position on AGW.

http://planetark.org/dailynewsstory.cfm?newsid=36492&newsdate=23-May-2006

"I believe the petroleum industry should actively engage in policy debate on climate change as well as play an active role in developing and implementing carbon management technologies to meet future challenges," Saudi Aramco president and CEO, Abdallah Jumah, told the meeting.

"National oil companies -- like Saudi Aramco -- can make meaningful contributions to those efforts," he said.

The oil industry accounts for up to 40 percent of carbon dioxide increase in the atmosphere which scientists believe is the prime cause of global warming, Robert Socolow of Princeton University said on the sidelines of the meeting.

Aramco officials said the company had already begun research on removing carbon dioxide given off by oil during shipping in tankers and filling empty oilfields with the unwanted gas instead of salt water.

"We are beginning to see in the oil industry ... some companies making that (reducing carbon emission) part of their strategies," said Adnan Shihab-Eldin, former secretary-general of oil producer cartel OPEC.

Is this the beginning of a more general acceptance of AGW and the start of serious efforts to mitigate the possible consequences?

 

[Mech_Engineer]

Man, this thread is going to wander on forever... And I do mean wander... The emotion is still running high, but the "evidence," if it can be called that, is growing thin. Perhaps we are beginning to revisit the stongest arguments of pgs. 1-3?

I'd like to state that after reading through this entire thread (all 6 pages of it, thus far. I'll bet it will hit 20 at this rate...) there have been arguments for and against AGW, but the fact is there is no definitive end-all evidence for or against it. Data is still being taken, and as our methods imporve, so too will our predictions.

I like to think of the overall consensus on climate change as a uniform standard deviaition curve: most of the arguments are in the middle, and they taper off as we get closer to "AGW is happening, no doubt about it" or "AGW is a crock, we can't change the planet." The overall average of the arguments is a big fat ZERO, wherever someone is arguing within the curve.

The only thing I can definitively say is that the Earth's climate, in some form or another, will continue on with or without our discussion. Earth is definitely NOT going to turn into Venus, and "Waterworld" and "The Day After Tomorrow" are at the very edges of my standard distribution. Man, it's going to be cool when we look back at times like this 10 or 25 or 50 years down the road and laugh at how misguided we were

Sorry to interrupt the heated debate (if it can still be called that), I'm going to move on to greener pastures. Something like Thermodynamics is actually quite refreshing after mucking through AGW debates...

 

[Skyhunter]

Atlantic conveyor moves heat northward to the tune of 1015W; current through the Bering Strait moves heat northward into the Chukchi Sea at 4x1013W. Atlantic heat keeps Europe warm enough to be inhabitable. The heat transferred to the Chukchi from N. Pac. is then transferred to Siberia by the southwesterly surface winds (driven by the north polar atmospheric circulation cell and coriolis effects). Average depth of the Bering Strait is around 50m; sea level rise over the past century is 10-20 cm; flow increase is 0.2-0.4% --- water temperatures in N. Pac. haven't changed that much, so heat flow has increased by same amount, 0.2-0.4W/m2 over the area of the Chukchi. Average insolation above the Arctic Circle? 15-20W/m2. Increase "expected" due to "GHW?" Around 1%, 0.2W/m2. Sea level rise is real. The north polar atmospheric convection is real. GHW should affect the entire Arctic Circle uniformly, not in spots.

I agree that the oceans are responsible for the thawing that is happening in the Arctic. I just think it is more the Atlantic ocean.

http://www.answers.com/topic/arctic-ocean

Since the Arctic's connection with the Pacific Ocean is narrow and very shallow, its principal exchange of water is with the Atlantic Ocean through the Greenland Sea. Even there, though surface waters communicate freely and a strong subsurface current brings warm water from the Atlantic into the Arctic basin, exchange of deeper waters is barred by submarine ridges. Thus a near stagnant pool of very cold water is found at the bottom of the Arctic basin.

And as you can see by this map the Norwegian current would bring much more warm heat into the Arctic Ocean than would spill over the Bering Strait.

This is interesting, and I believe supports my argument.

http://www.fou.uib.no/fd/1997/f/406001/

Ocean Weather Ship Station M
(66°N, 2°E)
The longest existing homogeneous time series from the deep ocean

The low temperature of the Norwegian Sea Deep Water (NSDW) is maintained by the contribution of the Greenland Sea Deep Water (GSDW). The bottom water in the Greenland Sea is renewed locally by surface cooling of relative fresh water, resulting in the coldest bottom water found in the deep ocean. NSDW is formed by mixing GSDW and the deep water from the Arctic Ocean. The recent warming of the NSDW has its forerunner in an even more markedly warming of the GSDW, see figure 5, consonant with the idea that the deep water formation in the Greenland Sea has ceased. The Greenland Sea and the Norwegian Sea basins are separated by the Mohn Ridge (Figure 1), and the exchange of water masses between the two deep basins takes place through a channel which has a threshold depth of 2200 m and is situated just north of Jan Mayen. Since the warming of GSDW appears to have continued unchecked to date, (Figure 5) the cessation of warming observed in the NSDW since 1990 is certainly unexpected, (Figure 4) suggesting that as GSDW production has (virtually) ceased, the transport through the Jan Mayen Channel may have reduced or even reversed, see figure 6, cutting off the deep Norwegian Sea from the influence of the GSDW and its changes, see Østerhus and Gammelsrød, 1996, and Østerhus et al., 1996.

 

[Skyhunter]

I'm going to move on to greener pastures.

Is that like cutting and running?

https://www.physicsforums.com/showpost.php?p=1006806&postcount=25

Oh man, this topic really gets me revved up...