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Recently Global Warming has been put into the spotlight once again by naysayers saying it is natural, humans have little impact, etc... and have accused governments and scientists of relaying falsified information.

One of the 'proofs' that scientists are falsifying their information, they say, is that we are currently in a global cooling situation and we are blowing it out of proportion. This video has a rather in-depth explanation on how exactly these sorts of things are misinterpreted by people who have an agenda or do not understand what is being said. As you can see, when you compare what was actually stated and what was interpreted in the talk show are completely different. It is not the scientists that are blowing it out of proportion, it is the media that are turning their backs to the truth. Here is the original powerpoint presentation relating to the video.

This video demonstrates the truth behind what exactly has been going on around the world, specifically in the arctic regions, for the last few decades. As you can see, the ice in the arctic polar region does not remain static year round. It recedes and advances according to the seasons. The time-lapsed video of arctic sea ice melt and depth shows that the thick sea ice of the arctic region has been decreasing year after year. The recent expansion of the sea ice, which has the naysayers in an uproar stating that global warming is a crock, isn't the thick sea ice in the time-lapse. It is thin sea ice and will advance and recede on a seasonal basis.

"Humans have very little impact on atmospheric CO2 levels and global warming"

The amount of CO2 in the atmosphere has been stated, by naysayers, to be caused mainly by volcanic activity not by human interaction with the environment. This is completely false. From the US Geological Survey Site:

Volcanoes release more than 130 million tonnes of CO2 into the atmosphere every year. This colorless, odorless gas usually does not pose a direct hazard to life because it typically becomes diluted to low concentrations very quickly whether it is released continuously from the ground or during episodic eruptions. But in certain circumstances, CO2 may become concentrated at levels lethal to people and animals. Carbon dioxide gas is heavier than air and the gas can flow into in low-lying areas; breathing air with more than 30% CO2 can quickly induce unconsciousness and cause death. In volcanic or other areas where CO2 emissions occur, it is important to avoid small depressions and low areas that might be CO2 traps. The boundary between air and lethal gas can be extremely sharp; even a single step upslope may be adequate to escape death.

Human activities release more than 130 times the amount of CO2 emitted by volcanoes--the equivalent of more than 8,000 additional volcanoes like Kilauea (Kilauea emits about 3.3 million tonnes/year)!

Additional confirmation that rising CO2 levels are due to human activity comes from examining the ratio of carbon isotopes found in the atmosphere. Carbon 12 has 6 neutrons, carbon 13 has 7 neutrons. Plants have a lower C13/C12 ratio than in the atmosphere. If rising atmospheric CO2 comes fossil fuels, the C13/C12 should be falling. Indeed this is what is occurring. (Ghosh 2003).

Another argument I've seen from the naysayers is that the CO2 level of the atmosphere was much higher in the past, such as when dinosaurs existed, than it is today and there was still life on the planet back then. The thing is is that dinosaurs were adapted to live in the environment in which they were in while humans and other like forms are adapted to live in their environment. Some of the impacts of too much intake of carbon dioxide into the lungs of humans are explained above, a condition known as Hypercapnia, a condition that those caught in the effects of volcanic eruptions have to be careful about. Current measurements indicate that the concentration of CO2 in fresh air varies from 0.036% to 0.039%. However greater amounts of CO2, such as those in crowded auditoriums, have been measured up to 1%. The U.S. Occupational Safety and Health Administration state that during an average workday, for safety concerns, exposure should not exceed 0.5%.

A recent survey of arctic sediments shows that the global warming of today is not the same as the global warming of past times. "The possibility that climate change might simply be a natural variation like others that have occurred throughout geologic time is dimming, according to evidence in a Proceedings of the National Academy of Sciences paper published October 19." from Arctic Sediments Show That 20th Century Warming Is Unlike Natural Variation

The Intergovernmental Panel on Climate Change (IPCC) is universally recognized as the world's most authoritative voice on the science on climate change. It was established by the United Nations and consists of over 2000 scientists from 100 different countries with the role of assessing the scientific, technical and socio-economic information relevant to climate change, as well as its potential impacts and options for adaptation and mitigation. This panel found that warming over the past 50 years is mainly a result of human interaction with the environment with it's findings publicly endorsed by the national academies of science of all G8 countries. (From the David Suzuki Foundation)

"Water Vapour, which accounts for approximately 98% of the greenhouse effect, completely nullifies the effect of the other greenhouse gasses in the atmosphere. It is just part of the Earth's normal climatic cycle."

I've seen variations of this statement time and time again from skeptics. It is true that without water vapour in the atmosphere the temperature of the Earth would drop significantly and, while it is the gas most significant to the greenhouse effect, the actual attributed percentage to the overall greenhouse effect is between 60% and 70%. (The number 98 came from a 1991 article by Richard Lindzen where he cites a 1990 IPCC report as his source. However the article doesn't appear to contain that number.)

The skeptic argument completely ignores the reactive nature of water. That being as heat increases a greater amount of evaporation takes place. We know, for example, that the atmospheric water over the oceans has increased by approximately 0.41 kilograms per square meter every ten years since 1988 (Santer et al. 2007).

Water vapour, while still having a significant impact on global warming, returns to the Earth as precipitation about 1 week after it enters the atmosphere. However CO2 stays around for 50 to 200 years and accounts, as of now, for about 25% of the greenhouse effect. The amount of CO2 in the atmosphere since the industrial revolution took off in the 1800's has risen from 280ppm to 376ppm. That is 77ppm above the highest concentrations attained during the last 400 thousand years (Source) and emissions have doubled since the 1990s (Source).

Warmed by CO2, the atmosphere is thus able to absorb more water vapor. And that water vapor, in turn, causes further warming—it amplifies the effects of carbon dioxide. So anthropogenic CO2 serves as the chief engine of global warming, with water vapor playing a crucial secondary role. According to the IPCC, if CO2 emissions were to double, water vapor would amplify the resulting temperature change by another 60 percent. Furthermore, a 2005 article in the journal Science forecast that the amount of water vapor in the upper troposphere will double by the end of this century, as a result of higher temperatures caused in part by the vapor itself. (Scientists refer to this situation as positive feedback.) (From Slate.com)

"Plants eat CO2! CO2 is a good thing!"

Yes plants do feed off of CO2. However there are other effects that would result in an increase of CO2 in the atmosphere. A greater uptake by carbon sinks and the greater acidification of those carbon sinks being one of them.

In any given region, the relative amounts of CO2 contained in the atmosphere and dissolved in the ocean's surface layer determine whether the ocean-water emits or absorbs gas. The amount of gas dissolved in the water is in turn influenced by the amount of phytoplankton (microscopic plants, particularly algae), which consume CO2 during photosynthesis. Increasingly acidic waters could stifle their supply of iron, a crucial nutrient.

Effect of Ocean Acidification on Iron Availability to Marine Phytoplankton

Bringing a little Canadian into this thread:

More than $200 billion worth of Canadian assets are at risk from global warming, says an international report released Monday.

The report, released jointly by a major insurance firm and an environmental group, ranked Canada as 12th in the world in terms of assets in jeopardy because of rising sea levels predicted by climate scientists.

But overall, it warned that the planet's atmosphere and ecosystems were close to dangerous ``tipping points'' that could affect hundreds of millions of people and cost hundreds of billions of dollars...

(source)

What is BC doing to counteract this?

“Electric cars are coming. They are in Europe and in Japan,” said Mayor Gregor Robertson, echoing observers who see that while Vancouver might lead Canada, it would be playing catch up to many cities elsewhere, such as San Francisco and Paris, which already each have hundreds of charging stations and growing culture for electric car use. “We need to be prepared.”

From The Vancouver Sun and Autobloggreen

The Nissan Leaf - Nissan LEAF is our first zero-emissions electric car. Don't confuse it with a hybrid or any other type of gas-powered, eco-friendly vehicle. This is electric - 100%. That means it burns zero gas and produces zero emissions. But this is no golf-cart. Off the line, Nissan LEAF performs like a V6. Plus, there's room for five, and it comes with all the quality, reliability and versatility you've come to expect from Nissan cars. and from CBC - A car that automaker Nissan hopes will revolutionize urban commuting made its Canadian debut in Vancouver Monday.

The Mitsubishi i MiEV - Mitsubishi plans to build about 2,000 i-MiEVs this year and up to 5,000 next year. The first i-MiEVs are going to corporate fleet customers in Japan this month. Closer to home, B.C. Hydro and the City of Vancouver have both agreed to add an i-MiEV to their fleets this November for "demonstration and evaluation purposes."

Green Power

However the electricity these vehicles use has to come from somewhere right? Despite the fact that BC Hydro, which serves an area containing 95% of BC residents, produces 80% of it's power through hydro-electric means it still owns 3 natural-gas fueled thermal power plants. The answer to the possibility of completely green sources of energy lies in the power of the wind.

BC has lagged behind other provinces, actually it's the last to implement a wind farm, with wind power technology. There has however, been a major step in the right direction. The first British Columbian wind farm began delivering power to the grid on August 6, 2009 (from CTV)and there are currently other farms being built around the province (from Canada.com).

Other possible sources of clean and renewable energy include wave power with BC having one of the greatest worldwide potentials for wave generated energy, tidal power such as the plant near the Orkney Islands in Scotland, and geothermal power that can make use of geothermally active areas such as Harrison Hot Springs.

Recent news has stated that BC is ready to make a big push to become a leading proponent of tidal power ( Source ) which will continue the provinces plan to become the forefront of clean energy production as laid out in the Clean Energy Act.

"British Columbia is blessed with enormous untapped energy potential," said the recent speech from the throne. "We can harness that potential to generate new wealth and new jobs in our communities while we lower greenhouse gas emissions within and beyond our borders. Clean energy is a cornerstone of our climate plan to reduce greenhouse gas emissions by one-third by the year 2020."

"A new clean energy act will encourage new investments in independent power production while also strengthening BC Hydro," said the throne speech. "It will provide for fair, predictable, clean power calls. It will feature simplified procurement protocols and new measures to encourage investment and the jobs that flow with it. "

From GlobalBC

Effects of Global Warming

A recent study by Bing Thom Architects has concluded that if the entire Greenland Ice Sheet were to melt it would effect several parts of Vancouver by putting them underwater. These include Granville Island, Kitsilano and Jericho beaches, the Stanley Park seawall, the Downtown Eastside, and the Port of Vancouver.

Yet another argument I've come across is that global warming is a product of the Sun, the sunspots on it and the amount of solar radiation it gives off. While the natural cycles of the Sun do play a minor role in the increasing or decreasing temperature of the Earth it is vastly over-exaggerated by the naysayers.

According to the NASA Goddard Institute for Space Studies (GISS):

"...the solar increases do not have the ability to cause large global temperature increases...greenhouse gases are indeed playing the dominant role..." (Source)

Did you know that the Sun emitted 1/3 less energy 4 billion years ago and has been brightening ever since yet it was quite a lot warmer in the past compared to the present? The reasoning is that there were higher levels of greenhouse gasses trapping more of the Sun's heat.

Sunspots work on an 11 year cycle with solar radiation fluctuating in between cycles due to the number of sunspots present. Solar measurements since 1978 have measured the Sun's activity and it's 11 year sunspot cycle. The studies show that there is very little correlation between the Sun's cycles and the rising and falling of temperature. (View data)

More recently released peer reviewed studies look closer at the relations between solar output and Earth climate relations and fully support the idea that the Sun is not the main driving factor for recent warming.

Recently there has been controversy over global warming due to some emails a hacker received from prominent British Scientists. The media then chose to pick and choose certain phrases and attempt to cast doubt on the data behind global warming and call into question the sources behind it, calling the incident 'climategate' after another well known scandle 'watergate'. The scientists in question have gone on record stating, "it was taken out of context."

Reactions:

The American Meteorological Society stated that the incident did not affect the society's position on climate change. They pointed to the breadth of evidence for human influence on climate, stating "For climate change research, the body of research in the literature is very large and the dependence on any one set of research results to the comprehensive understanding of the climate system is very, very small. Even if some of the charges of improper behavior in this particular case turn out to be true — which is not yet clearly the case — the impact on the science of climate change would be very limited."

Computerworld magazine cited the view of the RealClimate blog that what was not contained in the e-mails was the most interesting element: "There is no evidence of any worldwide conspiracy, no mention of George Soros nefariously funding climate research, no grand plan to 'get rid of the MWP' [Medieval Warm Period], no admission that global warming is a hoax, no evidence of the falsifying of data, and no 'marching orders' from our socialist/communist/vegetarian overlords." The science historian Spencer R. Weart, interviewed in the Washington Post, commented that the theft of the e-mails and the reaction to them was "a symptom of something entirely new in the history of science: Aside from crackpots who complain that a conspiracy is suppressing their personal discoveries, we've never before seen a set of people accuse an entire community of scientists of deliberate deception and other professional malfeasance. Even the tobacco companies never tried to slander legitimate cancer researchers."

Related External Links

RealClimate's Response - No doubt, instances of cherry-picked and poorly-worded “gotcha” phrases will be pulled out of context. One example is worth mentioning quickly. Phil Jones in discussing the presentation of temperature reconstructions stated that “I’ve just completed Mike’s Nature trick of adding in the real temps to each series for the last 20 years (ie from 1981 onwards) and from 1961 for Keith’s to hide the decline.” The paper in question is the Mann, Bradley and Hughes (1998) Nature paper on the original multiproxy temperature reconstruction, and the ‘trick’ is just to plot the instrumental records along with reconstruction so that the context of the recent warming is clear. Scientists often use the term “trick” to refer to a “a good way to deal with a problem”, rather than something that is “secret”, and so there is nothing problematic in this at all. As for the ‘decline’, it is well known that Keith Briffa’s maximum latewood tree ring density proxy diverges from the temperature records after 1960 (this is more commonly known as the “divergence problem”–see e.g. the recent discussion in this paper) and has been discussed in the literature since Briffa et al in Nature in 1998 (Nature, 391, 678-682). Those authors have always recommend not using the post 1960 part of their reconstruction, and so while ‘hiding’ is probably a poor choice of words (since it is ‘hidden’ in plain sight), not using the data in the plot is completely appropriate, as is further research to understand why this happens.

On the 'Divergence' Problem - An in depth article concerning the 'trick' many skeptics point to as evidence that climatologists are manipulating the data: An anomalous reduction in forest growth indices and temperature sensitivity has been detected in tree-ring width and density records from many circumpolar northern latitude sites since around the middle 20th century. This phenomenon, also known as the “divergence problem”, is expressed as an offset between warmer instrumental temperatures and their underestimation in reconstruction models based on tree rings. The divergence problem has potentially significant implications for large-scale patterns of forest growth, the development of paleoclimatic reconstructions based on tree-ring records from northern forests, and the global carbon cycle. Herein we review the current literature published on the divergence problem to date, and assess its possible causes and implications.

You can also view the entirety of the 2007 IPCC Fourth Assessment Report in the following links:

The AR4 Synthesis Report - Contribution of Working Groups I, II and III to the Fourth Assessment Report of the Intergovernmental Panel on Climate Change

WGI - The Physical Science Basis - Contribution of Working Group I to the Fourth Assessment Report of the Intergovernmental Panel on Climate Change

WGII - Impacts, Adaption and Vulnerability - Contribution of Working Group II to the Fourth Assessment Report of the Intergovernmental Panel on Climate Change

WGIII - Mitigation of Climate Change - Contribution of Working Group III to the Fourth Assessment Report of the Intergovernmental Panel on Climate Change

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Edit:

A prominent US climate scientist at the centre of the "climategate" leaked email controversy has been virtually cleared of professional misconduct by an internal university inquiry.

http://www.newscientist.com/article/dn18474-us-climategate-scientist-all-but-cleared-of-misconduct.html

Phil Jones has recently had an interview with BBC, unfortunately the skeptics have seen fit to quote mine his responses to make it seem like he is admitting to climate change fraud. Here is the real interview. Decide for yourself.

http://news.bbc.co.uk/2/hi/science/nature/8511670.stm

One of the questions taken from this interview and used by deniers deals with the year 1995 and Jones statement that there had been no statistically significant warming since 1995. Below is the question and answer.

Do you agree that from 1995 to the present there has been no statistically-significant global warming

Yes, but only just. I also calculated the trend for the period 1995 to 2009. This trend (0.12C per decade) is positive, but not significant at the 95% significance level. The positive trend is quite close to the significance level. Achieving statistical significance in scientific terms is much more likely for longer periods, and much less likely for shorter periods.

Note that this is not the same as saying there has been no warming. The term 'significant' in statistics does not relate to how much or how important something is but how likely it is to have occurred by chance. It's a function of the strength of the thing you're measuring, the background noise and the size of the sample. The significance level given is 93%, not 95% which is needed to achieve statistical significancy. This means that there is 93% probability that the trend is real and not chance. Of course a greater sample size or the longer you measure something will increase the significancy level due to the larger data set.

When methane(CH4), a colourless odorless gas formed by the decomposition of plant and animal matter, is burned in an engine combustion, or rapid oxidization, occurs forming carbon dioxide (CO2) and water (2H2O). Other fossil fuels, which are hydrocarbon based, have similar makeups and chemistry. The greenhouse effect occurs because some of the gases in the atmosphere, including both CO2 and water vapour, are able to absorb infrared radiation. While the energy the Earth receives from the Sun is mostly in the short (Ultraviolet) wavelength the energy that is re-emitted by the Earth's surface back out into space is in the long (Infrared) wavelength due to the temperature of the Earth's surface. Oxygen and nitrogen, the major gases in the atmosphere, do not have the ability to absorb IR radiation. However when infrared radiation strikes a molecule such as carbon dioxide it causes the bonds to bend and vibrate, known as the absorption of IR energy, and gain kinetic energy which it transfers to other molecules. The greater the concentration of these greenhouse gases that are in the atmosphere the greater this effect will be and the warmer the planet will become.

http://www.kcvs.ca/site/projects/common_files/IR_Spectrum/IR_spec5.swf

A link to a flash file dealing with greenhouse gasses (including water vapour) and radiative wavelength absorption.

It is well known that water vapour is the most dominant greenhouse gas in the atmosphere. The level of water vapour in the atmosphere is a function of temperature. This means that the more you increase the temperature of a given area the more evaporation will take place in that area and the greater amount of water vapour that area will be able to hold. This would result in rising temperatures which would increase commulatively until some other external force acts upon it. When other greenhouse gasses are added to the equation it amplifies this effect by increasing the transfer of heat.

Greenhouse gas absorption occurs in multiple levels of the atmosphere. It is not only limited to one layer. As the radiation re-emitted by the Earth's surface moves up layer by layer through the atmosphere some is stopped in each layer until eventually the energy reaches a layer so thin the radiation can escape into space unimpeded. When stopped, the molecule may radiate the energy back out into a random direction or it may transfer this energy into velocity in collisions with other air molecules, as explained above. As you add more greenhouse gases to the atmosphere and saturate the lower levels with greenhouse gases the mean radiating level of the planet will be set to higher altitudes. Approximately 99.13% of water vapour exists in the troposphere while CO2 can exist throughout the atmosphere.

A Saturated Gassy Argument
Increased Concentration and Vertical Distribution of Carbon Dioxide in the Stratosphere

Often disbelievers will state something similar to "CO2 (or greenhouse gasses) do not drive temperatures. Temps follow CO2 up to 800 years after the fact!" This mode of thinking concerns CO2 being the only driver for climate forcings, which is simply untrue. There are many reasons why temperature fluctuations can occur. CO2 is not always the main driver, it is merely the passenger that is along for the ride and heightens the effect. However, an instance where greenhouse gasses, including CO2, played a large role in rising temperatures is a period known as the Paleocene-Eocene Thermal Maximum. There are various possible theories as to the original forcing mechanism but it is very clear from the evidence that CO2 and other greenhouse gasses played a large role. The result was a 6 degree centigrade rise in temperatures over the course of 20,000 years and a mass extinction event.

The Paleocene-Eocene Thermal Maximum Gives Insight into Greenhouse Gas-Induced Environmental and Biotic Change

A climate forcing mechanism is one that will cause a change in climate while a feedback mechanism is one that will either be amplified (positive feedback) or dampened (negative feedback) due to these climate forcing mechanisms. There are four major climate change feedbacks according to literature by Bony et al (Bony et al 2006):

Water Vapour - When the air gets warmer the saturation vapour pressure of water increases. This means that as the air warms water vapour potential increases. As water vapour is a greenhouse gas the effects of the original climate forcing are heightened by the increase. (Watch Video)

Lapse Rate - The global mean tropospheric lapse rate is valued at roughly -6.5°/km to a height of between 10km to 15km. The Earths greenhouse effect and surface temperature tend to increase or decrease directly with the tropospheric lapse rate because this lapse rate affects the amount of longwave radiation into space. An atmosphere that warms more in the lower troposphere will produce a larger positive feedback whereas an atmosphere that warms faster at higher altitudes will produce a negative feedback. For more information click here.

Clouds - Probably the largest uncertainty of feedback mechanisms is that of clouds, a fact often taken up by deniers to support their conclusions that global warming is falsified. Clouds are both effective at absorbing and re-emitting long wave radiation from the Earth's surface and deflecting short wave radiation from the Sun. The feedback from clouds is influenced by cloud amount, cloud height and vertical profile, optical depth, liquid and ice water contents, and particle sizes. In todays climate models cloud feedback is either found to be a positive feedback or a neutral feedback (Held, Soden 2006).

Surface Albedo - Defined as the reflective strength of the Suns radiation by the surface of an object, the Earth's surface albedo is dependent on the type of ground cover. As the temperature of the planet warms highly reflective sources, such as snow and ice, melt and more absorption occurs resulting in a positive feedback.

A few more arguments I've come across

"The current cooling trend disproves global warming"

Basically, just as a few hot years don't prove global warming is real. A few cool years do not prove global warming is not real. If you look at the data in a longer time period you''ll see a slow rise in averaged temperatures. But they aren't steady, the trend looks more like a slinky that rises and dips according to the El Nino and La Nina cycles. The general direction, however, is still increasing. Many skeptics site 1998 as one of the warmest years on record and use this as an example of why global warming is a conspiracy. 1998 was one of the warmest years on record. It was also the time of the strongest El Nino on record. In reality the year 1998 is listed along with 2007 and 2009 as nearly tied for the warmest years on record. The warmest year on record was actually 2005. (Source and the accompanying graph) But why did these warming effects occur only to have those effects drop in time? This is specifically due to the El Nino and La Nina climactic and oceanic cycles, or the rising and falling of surface temperatures over the Pacific Ocean, and the increase and decrease of air pressure over those regions.


Global surface temperature anomalies relative to 1961‐1990 base period for three cases: HadCRUT, GISS, and GISS anomalies limited to the HadCRUT area. [To obtain consistent time series for the HadCRUT and GISS global means, monthly results were averaged over regions with defined temperature anomalies within four latitude zones (90N‐25N, 25N‐Equator, Equator‐25S, 25S‐90S); the global average then weights these zones by the true area of the full zones, and the annual means are based on those monthly global means.]
A NASA image courtesy of Realclimate.org

"Antarctica is getting cooler, not warmer, disproving global warming"

This refers to a 2002 study concluding between the years 1966 and 2000 Antarctica's interior cooled. A later study, which was much more in depth, showed that over a longer cycle the warming actually increased .5 degrees over those years. However this newer study does not contradict the 2002 study in any way. Actually the new study accepts and shows that east Antarctica, which the 2002 study was based on, showed cooling in those years given. (Another report by SCAR or the Scientific Committee on Antarctic Research in November of 2009 states an increase of .2 degrees since the 19th century.) But how can this occur? The cooling is due to the strengthening of the circular winds around the continent which prevent warmer air from reaching it's interior which seems to be a result of the cooling of the upper atmosphere due to the hole in the ozone layer above the pole. The hole is currently closing due cuts in CFC emissions and, as a result, the wind speed will die down significantly warming the area over the next decade or so.

Based on a new analysis of passive microwave satellite data, we demonstrate that the annual mean extent of Antarctic sea ice has increased at a statistically significant rate of 0.97% dec^−1 since the late 1970s. The largest increase has been in autumn when there has been a dipole of significant positive and negative trends in the Ross and Amundsen‐Bellingshausen Seas respectively. The autumn increase in the Ross Sea sector is primarily a result of stronger cyclonic atmospheric flow over the Amundsen Sea. Model experiments suggest that the trend towards stronger cyclonic circulation is mainly a result of stratospheric ozone depletion, which has strengthened autumn wind speeds around the continent, deepening the Amundsen Sea Low through flow separation around the high coastal orography. (Source)

The following NASA picture, originally released in 2006, showing the Antarctic temperature trend between 1981 and 2004 shows that most of the continent has been cooling while the waters around the continent are actually warming. The newer version of this image which extends the data range through 2007, shows much less cooling and even slight warming over most of the blue shaded area in the image below. Both images are below.



Figure 1: An older NASA image of temperature trends over Antarctica and the Southern Ocean. This image was first published on April 27, 2006 and was based on data from 1981-2004



Figure 2: The new version extends the data range through 2007, and was based on a revised analysis that included better inter-calibration among all the satellite records that are part of the time series. Image credit: NASA

The most recent study done on the antarctic ice sheet shows that while the interior has increased in thickness due to the wind cycles mentioned above, overall it actually shrank by 152 ± 80 cubic km between 2002 and 2005 which is equivalent to 0.4 ± 0.2 millimeters of global sea-level rise per year.



Antarctic ice loss between 1996 and 2006, overlaid on a Moderate Resolution Imaging Spectroradiometer (MODIS) mosaic image of Antarctica. The colors indicate the speed of the ice loss. Purple/red is fast. Green is slow. Image credit: NASA

"It's cold this winter. Global warming is a sham."

The current weather trend is just that, a weather trend, not a climactic trend. The weather trend is due to a phenomenon called the Arctic oscillation, a climate pattern that influences weather in the northern hemisphere.


The Arctic Oscillation is a climate pattern that influences winter weather in the Northern Hemisphere. It is defined by the pressure difference between air at mid-latitudes (around 45 degrees North, about the latitude of Montreal, Canada or Bordeaux, France) and air over the Arctic. A low-pressure air mass dominates the Arctic, while high pressure systems sit over the mid-latitudes. The strength of the high- and low-pressure systems oscillates. When the systems are weaker than normal, the pressure difference between the Arctic and mid-latitudes decreases, allowing chilly Arctic air to slide south while warmer air creeps north. A weaker-than-normal Arctic Oscillation is said to be negative. When high and low pressure systems are strong, the Arctic Oscillation is positive.

Throughout December 2009, the North Atlantic Oscillation was strongly negative, said the National Weather Service. This image shows the impact of the negative Arctic Oscillation on land surface temperatures throughout the Northern Hemisphere as observed by the Moderate Resolution Imaging Spectroradiometer (MODIS) on NASA’s Terra satellite. Cold Arctic air chilled the land surface at midlatitudes, while Arctic land, such as Greenland and Alaska, was much warmer than usual.




Arctic Oscillation (AO) Index. Positive values of the AO index indicate high low pressure in the polar region and thus a tendency for strong zonal winds that minimize cold air outbreaks to middle latitudes. Blue dots are monthly means and the red curve is the 60‐month (5‐year) running mean. (Notice the blue dot near the lowest point for the past year?)
A NASA image courtesy of Realclimate.org



Image courtesy of NSIDC: artwork by J. Wallace, University of Washington

So, what has been going on out there these past two months? As for the Arctic winter weather, it is exactly that -- Arctic. A pattern of high sea-level pressure over the Arctic has led to weaker westerly winds that typically pin cold air closer to the North pole. According to John M. Wallace, an atmospheric sciences professor at the University of Washington, the weakened jet stream has allowed cold Arctic air to creep into more southern latitudes over the U.S., Canada, Europe and Asia.

This pattern of pressure is called the “Arctic Oscillation.” The oscillation comes in two phases: a “negative phase” where there is relatively high pressure over the North pole and low pressure at the mid-latitudes (at about 45 degrees North); and a “positive phase” in which this pressure system is reversed. This winter, the Arctic Oscillation has been in an extremely negative state. This has caused unseasonably cold air masses to sweep over what are normally temperate latitudes, and unusually mild air masses to be brought in over much of the Arctic itself, Wallace explained.

Cold Snaps Plus Global Warming Do Add Up

"NASA made an error! 1934 is now the warmest year on record!"

This claim comes about because on August 4, 2007 when a blogger on the RealClimate.org website sent an email to NASA asserting that after 1999 the data was not being adjusted for time of day readings. This coincided with a switch in two sources of US temperature data. "The net effect of the change was to reduce mean U.S. anomalies by about 0.15 degrees Celsius for the years 2000-2006", said NASA climate modeler Gavin Schmidt.

"A minor data processing error found in the GISS temperature analysis in early 2007 does not affect the present analysis. The data processing flaw was failure to apply NOAA adjustments to United States Historical Climatology Network stations in 2000-2006, as the records for those years were taken from a different data base (Global Historical Climatology Network). This flaw affected only 1.6% of the Earth's surface (contiguous 48 states) and only the several years in the 21st century.

The data processing flaw did not alter the ordering of the warmest years on record and the global ranks were unaffected. In the contiguous 48 states, the statistical tie among 1934, 1998 and 2005 as the warmest year(s) was unchanged. In the current analysis, in the flawed analysis, and in the published GISS analysis, 1934 is the warmest year in the contiguous states (but not globally) by an amount (magnitude of the order of 0.01°C) that is an order of magnitude smaller than the certainty."

The above couple paragraphs appears on this page at the bottom of the article. Note that many denialist websites also claim that the temperature data was specifically for the US yet they go on to claim the entire world average was affected significantly.

The drought of the 1930s was known as the 'dust bowl' which lasted from 1931 to 1939 and merely added another problem on top of what was already a recession at the time. The dust bowl was most likely caused by cooler tropical Pacific Ocean temperatures combined with warmer tropical Atlantic Ocean temperatures which forced the jetstream to take a more southerly route across northern Mexico not allowing those high pressure systems associated with it to reach the center of the United States and small parts of Canada.

http://www.nasa.gov/centers/goddard/news/topstory/2004/0319dustbowl.html

"CO2 is already saturated"

This refers to skeptics claims that the amount of CO2 and water vapour in the atmosphere is already absorbing all of the radiation at the wavelengths related to CO2 absorption. They conclude that adding more CO2 to the atmosphere would thus have no effect. This theory however is wrong. As stated previously, CO2 exists throughout the troposphere and stratosphere while over 90% of water vapour exists in the troposphere. Higher altitudes is where CO2 absorption increases while water vapour decreases. (Source)

Satellites and spacecraft are capable of measuring outbound radiative wavelengths. Measurements show that outbound radiative wavelengths associated with CO2 and methane absorption have been decreasing. (Source)

Other consequences of rising CO2 and Global Warming as a result of man's use of fossil fuels

Ocean Acidification

Oceans absorb approximately 25% - 50% of man's emissions of CO2 annually as a result of the burning of fossil fuels. However, once CO2 mixes with sea water it dissolves making the oceans increasingly acidic. As the concentration of atmospheric CO2 rises so does the acidity of the ocean. Since the onset of the industrial revolution ocean acidification has risen by about 30% with half of the occurring only in the past 30 years. The increased acidity is adversely affecting marine corals and shell forming organisms to build their skeletal material and may also be affecting development of other marine organisms.

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Rising Sea Levels

Global mean sea level has been rising at an average rate of 1.7 mm/year (+/- 0.5mm) over the past century due to thermal expansion alone. The melting of the glaciers atop the Antarctic and Greenland land masses have assisted sea level rise even further between 10 and 20 cm.

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