Science (Part 2)
Tuesday 25th April, 2006 00:17 Comments: 0
In a recent email to Jessica I mentioned that I\'d recently ready State of Fear by Michael Crichton, and instead of being somewhat concerned about global warming, the Kyoto Protocol, and how the US weren\'t signed up to it, I\'m now a lot less worried. The gist is that global warming might not be happening. Sound crazy? Well it could be true:
IPCC draws firm conclusions unjustified by the science, especially given the acknowledged weakness of cloud physics in the climate models. For example, even those who accept that there is a warming trend point out that there is a big difference between correlation and causality. In other words, just because temperatures have generally been rising since the beginning of the Industrial Revolution, that doesn\'t necessarily mean that the Industrial Revolution has caused the change in temperature (see post hoc, ergo propter hoc argument). On the other hand, the period since the beginning of the Industrial Revolution has indeed produced ever-growing "urban heat islands" (see below) that could be skewing temperature measurements that indicate the recent warming.
Using "consensus" as evidence is an appeal to the majority argument rather than scientific discussion (see consensus science). Ergo, because the issue has become so politicized, it is suspected that climatologists who disagree with the consensus as it is may be afraid to speak out for fear of losing their positions or funding.
Consensus is further compromised in this field of study due to students being attracted to the field by their belief that something should be done about global warming. They complete their education and add their voices to the consensus, which gives a perceived bias.
Earth's climate has been both colder and warmer than today, and these changes are adequately explained by mechanisms that do not involve human greenhouse gas emissions.
There is no significant global warming relative to the expected natural trends.
CO2 in the atmosphere is mainly volcanic in origin, accounting for 97% of the CO2 found in the atmosphere, most of which travels to the oceans. Estimates at CO2's effectiveness as a greenhouse gas vary, but are generally around 10-100 times lower than water weight for weight, leaving a "net" greenhouse effect of man-made CO2 emissions at less than 1%
Climate science can not make definitive predictions yet, since the computer models used to make these predictions are still evolving and do not yet take into account recently discovered feedback mechanisms.
Climate models will not be able to predict the future climate until they can predict solar and volcanic activity.
Some global warming studies have errors or have not been reproduced.
Global temperatures are directly related to such factors as: sunspot activity (an 11-year cycle).
The concern about global warming is analogous to the concern about global cooling in the 1970s. The concern about global cooling was unnecessarily alarmist. The concern about global warming is equally alarmist.
So, the important question is whether the opponents could be right. Environmental groups, many governmental reports, and the non-US media often claim virtually unanimous support for the global warming theory from the scientific community. Some opponents maintain that it is the other way around, claiming that the majority of scientists either consider global warming "unproven" or even dismiss it altogether. Other opponents decry the dangers of consensus science, which appears to imply that they do believe there may actually be a consensus. Don\'t forget that everyone used to think the world was flat, and that the Sun orbited Earth, so you can\'t always believe the majority.
Global Warming and Carbon Dioxide
One argument against anthropogenic global warming questions the contention that rising levels of carbon dioxide and other greenhouse gases (GHGs) correlate with - and thus have caused - global warming. Proponents of the view that greenhouse gases have caused recent global warming respond that correlation is not a significant part of the evidence. Correlation is not causation. Indeed, studies of ice age temperature variations show carbon dioxide levels increasing after warming rather than before. This however assumes that current climate change can be expected to be like past climate change. While it is generally agreed that past (ice age) variations are timed by astronomical forcing; the current variations, of whatever size, are claimed to be timed by anthropogenic releases of CO2 (thus returning the argument to the importance of human CO2 emissions). Most warming during the past century took place before most carbon dioxide had been released. Between 1940 and 1970, global temperatures went down even though carbon-dioxide levels went up.
Urban Heat Islands
Global warming skeptics question the accuracy of the temperature records. They say if the monitoring stations are located in more populated areas, they must be influenced by the increased heat generated by the city as a whole (known as the "Urban heat island effect"). Those who believe in the accuracy of the records point out their consistency with the unaffected marine record; the lack of a difference between the warmings observed in urban and rural areas; and various studies which have examined the records and found no bias.
Global Warming and Solar Activity
Another point of controversy regarding anthropogenic global warming is the investigation of temperature correlations with the solar variation. This subject is a point of controversy between supporters and opponents of anthropogenic global warming.
There is also disagreement on whether the effects of global warming will be beneficial or detrimental. Many researchers predict disastrous consequences for a warming of 1.5 to 7 °C. The UN's Intergovernmental Panel on Climate Change (IPCC) predicts such a warming is likely within the 21st century, unless severe measures are taken. Other researchers feel that up to 1.5 °C of warming would increase crop yields and stabilize weather. Many of these doubt a larger warming is likely. In response, some advocates of strong early measures (well beyond Kyoto) note that the belief in beneficial effects and the doubt that a large warming is possible should be independent if these conclusions were in fact neutrally derived from scientific research.
New findings have suggested that the earth's climate system is inherently unstable, and that global warming could thus precipitate non-linear sudden climate shifts, as have been discovered to have occurred within the earth's past. Ocean circulation, believed to be the key to such climate shifts, has been observed to be slowing, causing alarm among oceanographers. Some scientists fear that the Gulf Stream, which conveys warm water from the Caribbean Sea across the Atlantic Ocean and is partly responsible for the relative mildness of northern Europe's climate (though other factors also predominate), could be reduced or stopped altogether by the decreased salt content of sea water resulting from global warming. This could cause temperatures in northern Europe to drop.
The US National Academy of Sciences issued a report on this phenomenon in 2002, titled Abrupt Climate Change - Inevitable Surprises (I wonder where the idea for the movie The Day After Tomorrow came from?). "It is important not to be fatalistic about the threats posed by abrupt climate change," it stated. "Societies have faced both gradual and abrupt climate changes for millennia and have learned to adapt through various mechanisms, such as moving indoors, developing irrigation for crops, and migrating away from inhospitable regions. Nevertheless, because climate change will likely continue in the coming decades, denying the likelihood or downplaying the relevance of past abrupt events could be costly."
So, basically, it still looks like no one has a f**king clue.
IPCC draws firm conclusions unjustified by the science, especially given the acknowledged weakness of cloud physics in the climate models. For example, even those who accept that there is a warming trend point out that there is a big difference between correlation and causality. In other words, just because temperatures have generally been rising since the beginning of the Industrial Revolution, that doesn\'t necessarily mean that the Industrial Revolution has caused the change in temperature (see post hoc, ergo propter hoc argument). On the other hand, the period since the beginning of the Industrial Revolution has indeed produced ever-growing "urban heat islands" (see below) that could be skewing temperature measurements that indicate the recent warming.
Using "consensus" as evidence is an appeal to the majority argument rather than scientific discussion (see consensus science). Ergo, because the issue has become so politicized, it is suspected that climatologists who disagree with the consensus as it is may be afraid to speak out for fear of losing their positions or funding.
Consensus is further compromised in this field of study due to students being attracted to the field by their belief that something should be done about global warming. They complete their education and add their voices to the consensus, which gives a perceived bias.
Earth's climate has been both colder and warmer than today, and these changes are adequately explained by mechanisms that do not involve human greenhouse gas emissions.
There is no significant global warming relative to the expected natural trends.
CO2 in the atmosphere is mainly volcanic in origin, accounting for 97% of the CO2 found in the atmosphere, most of which travels to the oceans. Estimates at CO2's effectiveness as a greenhouse gas vary, but are generally around 10-100 times lower than water weight for weight, leaving a "net" greenhouse effect of man-made CO2 emissions at less than 1%
Climate science can not make definitive predictions yet, since the computer models used to make these predictions are still evolving and do not yet take into account recently discovered feedback mechanisms.
Climate models will not be able to predict the future climate until they can predict solar and volcanic activity.
Some global warming studies have errors or have not been reproduced.
Global temperatures are directly related to such factors as: sunspot activity (an 11-year cycle).
The concern about global warming is analogous to the concern about global cooling in the 1970s. The concern about global cooling was unnecessarily alarmist. The concern about global warming is equally alarmist.
So, the important question is whether the opponents could be right. Environmental groups, many governmental reports, and the non-US media often claim virtually unanimous support for the global warming theory from the scientific community. Some opponents maintain that it is the other way around, claiming that the majority of scientists either consider global warming "unproven" or even dismiss it altogether. Other opponents decry the dangers of consensus science, which appears to imply that they do believe there may actually be a consensus. Don\'t forget that everyone used to think the world was flat, and that the Sun orbited Earth, so you can\'t always believe the majority.
Global Warming and Carbon Dioxide
One argument against anthropogenic global warming questions the contention that rising levels of carbon dioxide and other greenhouse gases (GHGs) correlate with - and thus have caused - global warming. Proponents of the view that greenhouse gases have caused recent global warming respond that correlation is not a significant part of the evidence. Correlation is not causation. Indeed, studies of ice age temperature variations show carbon dioxide levels increasing after warming rather than before. This however assumes that current climate change can be expected to be like past climate change. While it is generally agreed that past (ice age) variations are timed by astronomical forcing; the current variations, of whatever size, are claimed to be timed by anthropogenic releases of CO2 (thus returning the argument to the importance of human CO2 emissions). Most warming during the past century took place before most carbon dioxide had been released. Between 1940 and 1970, global temperatures went down even though carbon-dioxide levels went up.
Urban Heat Islands
Global warming skeptics question the accuracy of the temperature records. They say if the monitoring stations are located in more populated areas, they must be influenced by the increased heat generated by the city as a whole (known as the "Urban heat island effect"). Those who believe in the accuracy of the records point out their consistency with the unaffected marine record; the lack of a difference between the warmings observed in urban and rural areas; and various studies which have examined the records and found no bias.
Global Warming and Solar Activity
Another point of controversy regarding anthropogenic global warming is the investigation of temperature correlations with the solar variation. This subject is a point of controversy between supporters and opponents of anthropogenic global warming.
There is also disagreement on whether the effects of global warming will be beneficial or detrimental. Many researchers predict disastrous consequences for a warming of 1.5 to 7 °C. The UN's Intergovernmental Panel on Climate Change (IPCC) predicts such a warming is likely within the 21st century, unless severe measures are taken. Other researchers feel that up to 1.5 °C of warming would increase crop yields and stabilize weather. Many of these doubt a larger warming is likely. In response, some advocates of strong early measures (well beyond Kyoto) note that the belief in beneficial effects and the doubt that a large warming is possible should be independent if these conclusions were in fact neutrally derived from scientific research.
New findings have suggested that the earth's climate system is inherently unstable, and that global warming could thus precipitate non-linear sudden climate shifts, as have been discovered to have occurred within the earth's past. Ocean circulation, believed to be the key to such climate shifts, has been observed to be slowing, causing alarm among oceanographers. Some scientists fear that the Gulf Stream, which conveys warm water from the Caribbean Sea across the Atlantic Ocean and is partly responsible for the relative mildness of northern Europe's climate (though other factors also predominate), could be reduced or stopped altogether by the decreased salt content of sea water resulting from global warming. This could cause temperatures in northern Europe to drop.
The US National Academy of Sciences issued a report on this phenomenon in 2002, titled Abrupt Climate Change - Inevitable Surprises (I wonder where the idea for the movie The Day After Tomorrow came from?). "It is important not to be fatalistic about the threats posed by abrupt climate change," it stated. "Societies have faced both gradual and abrupt climate changes for millennia and have learned to adapt through various mechanisms, such as moving indoors, developing irrigation for crops, and migrating away from inhospitable regions. Nevertheless, because climate change will likely continue in the coming decades, denying the likelihood or downplaying the relevance of past abrupt events could be costly."
So, basically, it still looks like no one has a f**king clue.