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The Climate Change Thread
- Thread starter afransen
- Start date
Zephyr
Active Member
H
Hydrogen
Guest
A really long-winded and indirect restatement of the precautionary principle. Nothing novel or new.
Zephyr
Active Member
.
I would hope people who see this video are aware that this presentation in this form was part of its humour. The 'long-winded' discussion of the subject by everyone involved is part of what he mocks in that humour. He takes it a step further with barely a breath between his rapid-fire sentences and jarring edits.I especially enjoyed in another video, of the many that he has produced, where a handwritten cardboard placard with a list of sceptic/skeptic scientists is constantly flashed on the screen. His way of dealing with their brand of scientific inquiry in that video, while wearing one of his many outrageous hats, is unbearably funny. Yesterday in my Chicago office, before we were all disbanded after a mandatory year-end meeting, I asked a number of SEs in to view this video. They were straightaway on the floor laughing, verifying for me that I was not alone in being entertained.
In his expanded editions, he actually deals with several of the scientific issues contained within the debate; he also manages to list the typical questions (FAQs) that float around and for which there are responsible ways to address. Mind you, he is still "in character," which may be too much for those who are unamused.
Thanks again afransen for getting me started on the first of the many. (BTW, I was delighted at the number of 'hits' this video has received on YouTube since it went up - 'hits' in more ways than one.
).
afransen
Senior Member
I find that interesting, Hydrogen. It seems your whole position is that the science isn't certain, so no action is indicated. That is a fundamentally flawed idea.
H
Hydrogen
Guest
I said that the video was a long-winded restatement of the precautionary principle, and that it was nothing novel or new. That's all I said here, as I was commenting on the video.
From your reply, you appear to think that one ought to act on the basis of incomplete or inaccurate knowledge - or as a result of fearful imaginings of what the future might be like (irrational thinking). It might be important for you to note that the IPCC itself has indicated that an anthropogenic effect on global temperature increase has not been identified. The IPCC also notes that climate has always varied over time, and that more research is necessary to identify the evidence of a human impact. Such a statement has appeared in all four reports, it just doesn't make the headlines.
Talk about flawed thinking.
From your reply, you appear to think that one ought to act on the basis of incomplete or inaccurate knowledge - or as a result of fearful imaginings of what the future might be like (irrational thinking). It might be important for you to note that the IPCC itself has indicated that an anthropogenic effect on global temperature increase has not been identified. The IPCC also notes that climate has always varied over time, and that more research is necessary to identify the evidence of a human impact. Such a statement has appeared in all four reports, it just doesn't make the headlines.
Talk about flawed thinking.
afransen
Senior Member
"you appear to think that one ought to act on the basis of incomplete or inaccurate knowledge - or as a result of fearful imaginings of what the future might be like (irrational thinking)"
All human decisions are made in this manner. Only theoretical constructs assume perfect information. And like it or not, fear is an overriding factor in human decision making, at least when the stakes are high. This is what gives rise to the insurance industry, after all. Risk aversion is a more accurate term than fear, really. Rationality, in the form I suspect you referring to is what is referred to in game theory as von Neumann-Morgenstern preferences--that a rational agent will select the alternative with the maximum utility, where the utility of an option is equal to the sum of the value of each outcome multiplied by the probability that that outcome occurs. Humans, of course, usually don't know these probabilities for any reasonably complicated decision (beyond rolling fair dice, etc.); in other words, human can't behave in this way without estimating probabilities based on imperfect information. Beyond that, there is plenty of empirical evidence that suggests humans don't choose actions in this way, in that we have a strong aversion to risk. An illustration is that most middle-income individuals would take $1 million in guaranteed cash over a 50/50 chance of $2.5 million or $0.
The simple fact remains that it wouldn't be that painful to substantially reduce carbon emissions over the medium term. Even in the absence of human-caused global warming effect, the negative environmental impact of fossil fuel extraction and combustion is well-known, though perhaps not to its full extent. Accordingly, making the necessary policy changes to give rise of alternate sources of energy in a cost effective manner seems prudent, even if there is only a slight risk that increased CO2 concentrations in the atmosphere will cause global climate change. The stakes are pretty high, so it isn't terribly unreasonable to implement policies such as a carbon tax (offset by PIT and CIT reductions and transfers to low-income individuals). Economically speaking, a carbon tax makes more sense than any sort of tax on income or investment. Potentially avoiding the utter ecological collapse of northern Alberta and a reduction in atmospheric pollution are nice fringe benefits...
All human decisions are made in this manner. Only theoretical constructs assume perfect information. And like it or not, fear is an overriding factor in human decision making, at least when the stakes are high. This is what gives rise to the insurance industry, after all. Risk aversion is a more accurate term than fear, really. Rationality, in the form I suspect you referring to is what is referred to in game theory as von Neumann-Morgenstern preferences--that a rational agent will select the alternative with the maximum utility, where the utility of an option is equal to the sum of the value of each outcome multiplied by the probability that that outcome occurs. Humans, of course, usually don't know these probabilities for any reasonably complicated decision (beyond rolling fair dice, etc.); in other words, human can't behave in this way without estimating probabilities based on imperfect information. Beyond that, there is plenty of empirical evidence that suggests humans don't choose actions in this way, in that we have a strong aversion to risk. An illustration is that most middle-income individuals would take $1 million in guaranteed cash over a 50/50 chance of $2.5 million or $0.
The simple fact remains that it wouldn't be that painful to substantially reduce carbon emissions over the medium term. Even in the absence of human-caused global warming effect, the negative environmental impact of fossil fuel extraction and combustion is well-known, though perhaps not to its full extent. Accordingly, making the necessary policy changes to give rise of alternate sources of energy in a cost effective manner seems prudent, even if there is only a slight risk that increased CO2 concentrations in the atmosphere will cause global climate change. The stakes are pretty high, so it isn't terribly unreasonable to implement policies such as a carbon tax (offset by PIT and CIT reductions and transfers to low-income individuals). Economically speaking, a carbon tax makes more sense than any sort of tax on income or investment. Potentially avoiding the utter ecological collapse of northern Alberta and a reduction in atmospheric pollution are nice fringe benefits...
Zephyr
Active Member
Which set of IPCC reports make these statements to which you refer (especially the year)? And where in them is any of this actually stated?
I don't think this is asking too much, since you obviously read this already. I also am assuming that you are current on what their positions are on a number of related issues, as you highlight these issues in particular for this post.
H
Hydrogen
Guest
I cited one such reference for you in another thread.
Are you up to date on the IPCC's own self-stated low-levels (their words) of understanding with respect to a range of climate forcing? They are considerable. The IPCC just does not come out and state these things very clearly in the section for policy makers, but they are in the document(s).
Are you up to date on the IPCC's own self-stated low-levels (their words) of understanding with respect to a range of climate forcing? They are considerable. The IPCC just does not come out and state these things very clearly in the section for policy makers, but they are in the document(s).
ganjavih
Senior Member
- Warming of the climate system is unequivocal.
- Most of the observed increase in globally averaged temperatures since the mid-20th century is very likely due to the observed increase in anthropogenic (human) greenhouse gas concentrations.
- Anthropogenic warming and sea level rise would continue for centuries due to the timescales associated with climate processes and feedbacks, even if greenhouse gas concentrations were to be stabilized, although the likely amount of temperature and sea level rise varies greatly depending on the fossil intensity of human activity during the next century (pages 13 and 18).
- The probability that this is caused by natural climatic processes alone is less than 5%.
IPCC Fourth Assessment Report: Climate Change 2007
- Most of the observed increase in globally averaged temperatures since the mid-20th century is very likely due to the observed increase in anthropogenic (human) greenhouse gas concentrations.
- Anthropogenic warming and sea level rise would continue for centuries due to the timescales associated with climate processes and feedbacks, even if greenhouse gas concentrations were to be stabilized, although the likely amount of temperature and sea level rise varies greatly depending on the fossil intensity of human activity during the next century (pages 13 and 18).
- The probability that this is caused by natural climatic processes alone is less than 5%.
IPCC Fourth Assessment Report: Climate Change 2007
Zephyr
Active Member
H
Hydrogen
Guest
With respect to their assertion for a high degree of certainty in understanding that humans alone are responsible for climate change, the IPCC lists a considerable set of uncertainties with respect to its own assertions for certainty and high confidence. The listing of these uncertainties can be found throughout the AFAR IPCC 2007, particularly in the chapters dealing with their selection of evidence to support their contention of the primacy of human causes. Some of the uncertainties briefly outlined in the Technical Summary of the AFAR are shown below.
The relative blandness of many of these stated uncertainties here and throughout the IPCC AFAR 2007 can obscure the fact that there is a considerable lack of understanding concerning the climate, and that as a result, model or scenario projections are actually very poor when employed as a means to predict the future. Interestingly, the IPCC once again indicates a very low level of scientific understanding with respect to natural causes for climate variability.
Of course, in this circumstance, the IPCC pays attention to only its own consideration for what constitutes an uncertainty. The document does not contain either any dissenting reports from its member scientists (and there are critical members of the IPCC); nor does it acknowledge direct criticism concerning its main assumption of change in climate due only - or primarily - to human activity.
IPCC uncertainties concerning changes in human and natural drivers of climate (p.81):
The full range of processes leading to modification of cloud properties by aerosols is not well understood and the magnitudes of associated indirect radiative effects are poorly determined.
The causes of, and radiative forcing due to stratospheric water vapour changes are not well quantified.
The geographical distribution and time evolution of the radiative forcing due to changes in aerosols during the 20th century are not well characterised.
The causes of recent changes in the growth rate of atmospheric CH4 are not well understood.
The roles of different factors increasing tropospheric ozone concentrations since pre-industrial times are not well characterised.
Land surface properties and land-atmosphere interactions that lead to radiative forcing are not well quantified.
Knowledge of the contribution of past solar changes to radiative forcing on the time scale of centuries is not based upon direct measurements and is hence strongly dependent upon physical understanding.
IPCC uncertainties concerning observations of changes in climate in the atmosphere and on the surface (p.82):
Radiosonde records are much less complete spatially than surface records and evidence suggests a number of radiosonde records are unreliable, especially in the tropics. It is likely that all records of tropospheric temperature trends still contain residual errors.
While changes in large-scale atmospheric circulation are apparent, the quality of analyses is best only after 1979, making analysis of, and discrimination between, change and variability difficult.
Surface and satellite observations disagree on total and low-level cloud changes over the ocean.
Multi-decadal changes in DTR are not well understood, in part because of limited observations of changes in cloudiness and aerosols.
Difficulties in the measurement of precipitation remain an area of concern in quantifying trends in global and regional precipitation.
Records of soil moisture and streamflow are often very short, and are available for only a few regions, which impedes complete analyses of changes in droughts.
The availability of observational data restricts the types of extremes that can be analysed. The rarer the event, the more difficult it is to identify long-term changes because there are fewer cases available.
Information on hurricane frequency and intensity is limited prior to the satellite era. There are questions about the interpretation of the satellite record.
There is insufficient evidence to determine whether trends exist in tornadoes, hail, lightning and dust storms at small spatial scales.
IPCC uncertainties concerning snow, ice and frozen ground (p.83):
There is no global compilation of in situ snow data prior to 1960. Well-calibrated snow water equivalent data are not available for the satellite era.
There are insufficient data to draw any conclusions about trends in the thickness of Antarctic sea ice.
Uncertainties in estimates of glacier mass loss arise from limited global inventory data, incomplete area-volume relationships and imbalance in geographic coverage.
Mass balance estimates for ice shelves and ice sheets, especially for Antarctica, are limited by calibration and validation of changes detected by satellite altimetry and gravity measurements.
Limited knowledge of basal processes and of ice shelf dynamics leads to large uncertainties in the understanding of ice flow processes and ice sheet stability.
IPCC uncertainties concerning oceans and sea levels (p. 84):
Limitations in ocean sampling imply that decadal variability in global heat content, salinity and sea level changes can only be evaluated with moderate confidence.
There is low confidence in observations of trends in the MOC.
Global average sea level rise from 1961 to 2003 appears to be larger than can be explained by thermal expansion and land ice melting.
IPCC uncertainties in the paleoclimate record with respect to the IPCC presentation (p.85):
Mechanisms of onset and evolution of past abrupt climate change and associated climate thresholds are not well understood. This limits confidence in the ability of climate models to simulate realistic abrupt change.
The degree to which ice sheets retreated in the past, the rates of such change and the processes involved are not well known.
Knowledge of climate variability over more than the last few hundred years in the SH and tropics is limited by the lack of palaeoclimatic records.
Differing amplitudes and variability observed in available millennial-length NH temperature reconstructions, as well as the relation of these differences to choice of proxy data and statistical calibration methods, still need to be reconciled.
The lack of extensive networks of proxy data for temperature in the last 20 years limits understanding of how such proxies respond to rapid global warming and of the influence of other environmental changes.
IPCC uncertainties in the attributing climate change to human activity (p.86):
Confidence in attributing some climate change phenomena to anthropogenic influences is currently limited by uncertainties in radiative forcing, as well as uncertainties in feedbacks and in observations.
Attribution at scales smaller than continental and over time scales of less than 50 years is limited by larger climate variability on smaller scales, by uncertainties in the small-scale details of external forcing and the response simulated by models, as well as uncertainties in simulation of internal variability on small scales, including in relation to modes of variability.
There is less confidence in understanding of forced changes in precipitation and surface pressure than there is of temperature.
The range of attribution statements is limited by the absence of formal detection and attribution studies, or their very limited number, for some phenomena (e.g., some types of extreme events).
Incomplete global data sets for extremes analysis and model uncertainties still restrict the regions and types of detection studies of extremes that can be performed.
Despite improved understanding, uncertainties in model simulated internal climate variability limit some aspects of attribution studies. For example, there are apparent discrepancies between estimates of ocean heat content variability from models and observations.
Lack of studies quantifying the contributions of anthropogenic forcing to ocean heat content increase or glacier melting together with the open part of the sea level budget for 1961 to 2003 are among the uncertainties in quantifying the anthropogenic contribution to sea level rise.
IPCC uncertainties with respect to their modeling of future climate (p.87):
A proven set of model metrics comparing simulations with observations, that might be used to narrow the range of plausible climate projections, has yet to be developed.
Most models continue to have difficulty controlling climate drift, particularly in the deep ocean. This drift must be accounted for when assessing change in many oceanic variables.
Models differ considerably in their estimates of the strength of different feedbacks in the climate system.
Problems remain in the simulation of some modes of variability, notably the Madden-Julian Oscillation, recurrent atmospheric blocking and extreme precipitation.
Systematic biases have been found in most models’ simulations of the Southern Ocean that are linked to uncertainty in transient climate response.
Climate models remain limited by the spatial resolution that can be achieved with present computer resources, by the need for more extensive ensemble runs and by the need to include some additional processes.
IPCC uncertainties concerning climate equilibrium and transient climate sensitivity (p.88):
Large uncertainties remain about how clouds might respond to global climate change.
IPCC uncertainties concerning global projections (p.89):
The likelihood of a large abrupt change in the MOC beyond the end of the 21st century cannot yet be assessed reliably. For low and medium emission scenarios with atmospheric greenhouse gas concentrations stabilized beyond 2100, the MOC recovers from initial weakening within one to several centuries. A permanent reduction in the MOC cannot be excluded if the forcing is strong and long enough.
The model projections for extremes of precipitation show larger ranges in amplitude and geographical locations than for temperature.
The response of some major modes of climate variability such as ENSO still differs from model to model, which may be associated with differences in the spatial and temporal representation of present-day conditions.
The robustness of many model responses of tropical cyclones to climate change is still limited by the resolution of typical climate models.
Changes in key processes that drive some global and regional climate changes are poorly known (e.g., ENSO, NAO, blocking, MOC, land surface feedbacks, tropical cyclone distribution).
The magnitude of future carbon cycle feedbacks is still poorly determined.
Uncertainties concerning sea levels, according to the IPCC (p.90):
Models do not yet exist that address key processes that could contribute to large rapid dynamical changes in the Antarctic and Greenland Ice Sheets that could increase the discharge of ice into the ocean.
The sensitivity of ice sheet surface mass balance (melting and precipitation) to global climate change is not well constrained by observations and has a large spread in models. There is consequently a large uncertainty in the magnitude of global warming that, if sustained, would lead to the elimination of the Greenland Ice Sheet.
Key uncertainties concerning regional projections (p.90):
In some regions there has been only very limited study of key aspects of regional climate change, particularly with regard to extreme events.
Atmosphere-Ocean General Circulation Models show no consistency in simulated regional precipitation change in some key regions (e.g., northern South America, northern
Australia and the Sahel).
In many regions where fine spatial scales in climate are generated by topography, there is insufficient information on how climate change will be expressed at these scales.
MOC: Meridional Overturning Circulation: an overturning circulation of the ocean.
ENSO: El Nino-Southern Oscillation: a coupled ocean-atmosphere phenomenon (IPCC models have consistently failed to predict changes to the naturally-appearing ENSO).
NAO: North Atlantic Oscillation: an ocean oscillation.
DTR: Diurnal temperature range: the difference between the maximum and minimum temperature during a 24-hour period.
The relative blandness of many of these stated uncertainties here and throughout the IPCC AFAR 2007 can obscure the fact that there is a considerable lack of understanding concerning the climate, and that as a result, model or scenario projections are actually very poor when employed as a means to predict the future. Interestingly, the IPCC once again indicates a very low level of scientific understanding with respect to natural causes for climate variability.
Of course, in this circumstance, the IPCC pays attention to only its own consideration for what constitutes an uncertainty. The document does not contain either any dissenting reports from its member scientists (and there are critical members of the IPCC); nor does it acknowledge direct criticism concerning its main assumption of change in climate due only - or primarily - to human activity.
IPCC uncertainties concerning changes in human and natural drivers of climate (p.81):
The full range of processes leading to modification of cloud properties by aerosols is not well understood and the magnitudes of associated indirect radiative effects are poorly determined.
The causes of, and radiative forcing due to stratospheric water vapour changes are not well quantified.
The geographical distribution and time evolution of the radiative forcing due to changes in aerosols during the 20th century are not well characterised.
The causes of recent changes in the growth rate of atmospheric CH4 are not well understood.
The roles of different factors increasing tropospheric ozone concentrations since pre-industrial times are not well characterised.
Land surface properties and land-atmosphere interactions that lead to radiative forcing are not well quantified.
Knowledge of the contribution of past solar changes to radiative forcing on the time scale of centuries is not based upon direct measurements and is hence strongly dependent upon physical understanding.
IPCC uncertainties concerning observations of changes in climate in the atmosphere and on the surface (p.82):
Radiosonde records are much less complete spatially than surface records and evidence suggests a number of radiosonde records are unreliable, especially in the tropics. It is likely that all records of tropospheric temperature trends still contain residual errors.
While changes in large-scale atmospheric circulation are apparent, the quality of analyses is best only after 1979, making analysis of, and discrimination between, change and variability difficult.
Surface and satellite observations disagree on total and low-level cloud changes over the ocean.
Multi-decadal changes in DTR are not well understood, in part because of limited observations of changes in cloudiness and aerosols.
Difficulties in the measurement of precipitation remain an area of concern in quantifying trends in global and regional precipitation.
Records of soil moisture and streamflow are often very short, and are available for only a few regions, which impedes complete analyses of changes in droughts.
The availability of observational data restricts the types of extremes that can be analysed. The rarer the event, the more difficult it is to identify long-term changes because there are fewer cases available.
Information on hurricane frequency and intensity is limited prior to the satellite era. There are questions about the interpretation of the satellite record.
There is insufficient evidence to determine whether trends exist in tornadoes, hail, lightning and dust storms at small spatial scales.
IPCC uncertainties concerning snow, ice and frozen ground (p.83):
There is no global compilation of in situ snow data prior to 1960. Well-calibrated snow water equivalent data are not available for the satellite era.
There are insufficient data to draw any conclusions about trends in the thickness of Antarctic sea ice.
Uncertainties in estimates of glacier mass loss arise from limited global inventory data, incomplete area-volume relationships and imbalance in geographic coverage.
Mass balance estimates for ice shelves and ice sheets, especially for Antarctica, are limited by calibration and validation of changes detected by satellite altimetry and gravity measurements.
Limited knowledge of basal processes and of ice shelf dynamics leads to large uncertainties in the understanding of ice flow processes and ice sheet stability.
IPCC uncertainties concerning oceans and sea levels (p. 84):
Limitations in ocean sampling imply that decadal variability in global heat content, salinity and sea level changes can only be evaluated with moderate confidence.
There is low confidence in observations of trends in the MOC.
Global average sea level rise from 1961 to 2003 appears to be larger than can be explained by thermal expansion and land ice melting.
IPCC uncertainties in the paleoclimate record with respect to the IPCC presentation (p.85):
Mechanisms of onset and evolution of past abrupt climate change and associated climate thresholds are not well understood. This limits confidence in the ability of climate models to simulate realistic abrupt change.
The degree to which ice sheets retreated in the past, the rates of such change and the processes involved are not well known.
Knowledge of climate variability over more than the last few hundred years in the SH and tropics is limited by the lack of palaeoclimatic records.
Differing amplitudes and variability observed in available millennial-length NH temperature reconstructions, as well as the relation of these differences to choice of proxy data and statistical calibration methods, still need to be reconciled.
The lack of extensive networks of proxy data for temperature in the last 20 years limits understanding of how such proxies respond to rapid global warming and of the influence of other environmental changes.
IPCC uncertainties in the attributing climate change to human activity (p.86):
Confidence in attributing some climate change phenomena to anthropogenic influences is currently limited by uncertainties in radiative forcing, as well as uncertainties in feedbacks and in observations.
Attribution at scales smaller than continental and over time scales of less than 50 years is limited by larger climate variability on smaller scales, by uncertainties in the small-scale details of external forcing and the response simulated by models, as well as uncertainties in simulation of internal variability on small scales, including in relation to modes of variability.
There is less confidence in understanding of forced changes in precipitation and surface pressure than there is of temperature.
The range of attribution statements is limited by the absence of formal detection and attribution studies, or their very limited number, for some phenomena (e.g., some types of extreme events).
Incomplete global data sets for extremes analysis and model uncertainties still restrict the regions and types of detection studies of extremes that can be performed.
Despite improved understanding, uncertainties in model simulated internal climate variability limit some aspects of attribution studies. For example, there are apparent discrepancies between estimates of ocean heat content variability from models and observations.
Lack of studies quantifying the contributions of anthropogenic forcing to ocean heat content increase or glacier melting together with the open part of the sea level budget for 1961 to 2003 are among the uncertainties in quantifying the anthropogenic contribution to sea level rise.
IPCC uncertainties with respect to their modeling of future climate (p.87):
A proven set of model metrics comparing simulations with observations, that might be used to narrow the range of plausible climate projections, has yet to be developed.
Most models continue to have difficulty controlling climate drift, particularly in the deep ocean. This drift must be accounted for when assessing change in many oceanic variables.
Models differ considerably in their estimates of the strength of different feedbacks in the climate system.
Problems remain in the simulation of some modes of variability, notably the Madden-Julian Oscillation, recurrent atmospheric blocking and extreme precipitation.
Systematic biases have been found in most models’ simulations of the Southern Ocean that are linked to uncertainty in transient climate response.
Climate models remain limited by the spatial resolution that can be achieved with present computer resources, by the need for more extensive ensemble runs and by the need to include some additional processes.
IPCC uncertainties concerning climate equilibrium and transient climate sensitivity (p.88):
Large uncertainties remain about how clouds might respond to global climate change.
IPCC uncertainties concerning global projections (p.89):
The likelihood of a large abrupt change in the MOC beyond the end of the 21st century cannot yet be assessed reliably. For low and medium emission scenarios with atmospheric greenhouse gas concentrations stabilized beyond 2100, the MOC recovers from initial weakening within one to several centuries. A permanent reduction in the MOC cannot be excluded if the forcing is strong and long enough.
The model projections for extremes of precipitation show larger ranges in amplitude and geographical locations than for temperature.
The response of some major modes of climate variability such as ENSO still differs from model to model, which may be associated with differences in the spatial and temporal representation of present-day conditions.
The robustness of many model responses of tropical cyclones to climate change is still limited by the resolution of typical climate models.
Changes in key processes that drive some global and regional climate changes are poorly known (e.g., ENSO, NAO, blocking, MOC, land surface feedbacks, tropical cyclone distribution).
The magnitude of future carbon cycle feedbacks is still poorly determined.
Uncertainties concerning sea levels, according to the IPCC (p.90):
Models do not yet exist that address key processes that could contribute to large rapid dynamical changes in the Antarctic and Greenland Ice Sheets that could increase the discharge of ice into the ocean.
The sensitivity of ice sheet surface mass balance (melting and precipitation) to global climate change is not well constrained by observations and has a large spread in models. There is consequently a large uncertainty in the magnitude of global warming that, if sustained, would lead to the elimination of the Greenland Ice Sheet.
Key uncertainties concerning regional projections (p.90):
In some regions there has been only very limited study of key aspects of regional climate change, particularly with regard to extreme events.
Atmosphere-Ocean General Circulation Models show no consistency in simulated regional precipitation change in some key regions (e.g., northern South America, northern
Australia and the Sahel).
In many regions where fine spatial scales in climate are generated by topography, there is insufficient information on how climate change will be expressed at these scales.
MOC: Meridional Overturning Circulation: an overturning circulation of the ocean.
ENSO: El Nino-Southern Oscillation: a coupled ocean-atmosphere phenomenon (IPCC models have consistently failed to predict changes to the naturally-appearing ENSO).
NAO: North Atlantic Oscillation: an ocean oscillation.
DTR: Diurnal temperature range: the difference between the maximum and minimum temperature during a 24-hour period.
afransen
Senior Member
Hydrogen, none of that is important. It's all just smoke and mirrors to distract people from performing the risk analysis and moving forward. Given that there is some evidence of climate change, caused by humanity or not, and that there are reasonable theories or evidence to suggest at least some of it is related to human activity, it is entirely reasonable for us to take corrective action, even without scientific certainty (which isn't going to be arrived at any time soon).
This is how we've dealt with dozens of problems in the past, particular environmental problems, such as acid rain or PCBs affecting bird populations. We didn't have scientific certainty that these effects were related to human activity, but we took corrective action anyway.
My only concern at this point is that we change tacks from carbon trading to a system of carbon taxing. Trading emission credits is doomed to failure by some simple political and economic realities. I hope that people who try to stall action by obfuscating the issue and calling for us to wait until there is scientific certainty don't succeed.
This is how we've dealt with dozens of problems in the past, particular environmental problems, such as acid rain or PCBs affecting bird populations. We didn't have scientific certainty that these effects were related to human activity, but we took corrective action anyway.
My only concern at this point is that we change tacks from carbon trading to a system of carbon taxing. Trading emission credits is doomed to failure by some simple political and economic realities. I hope that people who try to stall action by obfuscating the issue and calling for us to wait until there is scientific certainty don't succeed.
H
Hydrogen
Guest
So the IPCC's own stated levels of uncertainty (which are actually considerable) is to be considered as "smoke and mirrors?" That's a rather incredible assessment.
Climate change is natural. The issue that has been obscured is whether the slight change in temperature over the last 100 years has been caused (in whole or in part) by human activity. There is no conclusive evidence for such a position. There is, however, a very well established range of evidence to show that natural climate change has existed throughout the history of the planet.
The question as to "why" things should be done is quite relevant with respect to this issue, and simple belief or worry are not a good enough basis for action given what is being demanded. The "problem" of climate change will not be solved, or corrected, by human action if it is not a problem. If anything, trying to solve a problem that does not exist, or is not caused by human activity, or is only partially caused by human action, can turn out to be nothing more than a massive expenditure of limited resources that will have very little impact of any sort. If anything, such an approach holds the potential to create many more problems.
As to the levels of certainty concerning sulfur dioxide emissions, lead, particulates and carbon monoxide, these were of a much higher order of understanding than that of anthropogenic global climate change. The effects of these emissions were much more localized and could be tracked with a greater degree of accuracy. Recently, volatile organic compounds and nitrogen oxides have been more clearly identified as issues of concern with respect to air quality. With the exception of nitrogen oxides, all of the above mentioned emissions have dropped considerably since 1974. Emissions of nitrogen oxides have remained roughly stable - since 1985.
Carbon dioxide as a gas presents no danger to human beings in the levels that it appears in the atmosphere. It is a molecule essential to life. The quantity of the gas that appears in the atmosphere has also changed over time - naturally. Periods of higher levels of carbon dioxide have also been associated with higher levels of biodiversity (and I am not suggesting anything with this point, just mentioning it). If anything carbon dioxide is at historically low levels when compared over longer geological periods.
Without accurate knowledge, how do you expect make useful decisions? I find it rather incredible in this day and age that people would wish to see action carried out on the basis of belief, fear or guilt. Questioning beliefs and a skeptical attitude are not obfuscation, they are qualities of critical thinking and inquiry.
Climate change is natural. The issue that has been obscured is whether the slight change in temperature over the last 100 years has been caused (in whole or in part) by human activity. There is no conclusive evidence for such a position. There is, however, a very well established range of evidence to show that natural climate change has existed throughout the history of the planet.
The question as to "why" things should be done is quite relevant with respect to this issue, and simple belief or worry are not a good enough basis for action given what is being demanded. The "problem" of climate change will not be solved, or corrected, by human action if it is not a problem. If anything, trying to solve a problem that does not exist, or is not caused by human activity, or is only partially caused by human action, can turn out to be nothing more than a massive expenditure of limited resources that will have very little impact of any sort. If anything, such an approach holds the potential to create many more problems.
As to the levels of certainty concerning sulfur dioxide emissions, lead, particulates and carbon monoxide, these were of a much higher order of understanding than that of anthropogenic global climate change. The effects of these emissions were much more localized and could be tracked with a greater degree of accuracy. Recently, volatile organic compounds and nitrogen oxides have been more clearly identified as issues of concern with respect to air quality. With the exception of nitrogen oxides, all of the above mentioned emissions have dropped considerably since 1974. Emissions of nitrogen oxides have remained roughly stable - since 1985.
Carbon dioxide as a gas presents no danger to human beings in the levels that it appears in the atmosphere. It is a molecule essential to life. The quantity of the gas that appears in the atmosphere has also changed over time - naturally. Periods of higher levels of carbon dioxide have also been associated with higher levels of biodiversity (and I am not suggesting anything with this point, just mentioning it). If anything carbon dioxide is at historically low levels when compared over longer geological periods.
Without accurate knowledge, how do you expect make useful decisions? I find it rather incredible in this day and age that people would wish to see action carried out on the basis of belief, fear or guilt. Questioning beliefs and a skeptical attitude are not obfuscation, they are qualities of critical thinking and inquiry.
afransen
Senior Member
All human actions have been based on beliefs about the state of the world, in the statistical sense. I think you mean degree of belief, or confidence.
I think the problem with your argument is that assumption that measures taken to reduce GHG emissions will be exceedingly detrimental to the economy. A gradually introduced, predictable (and preferably global) carbon tax need not be economically detrimental, and could indeed have fewer negative economic consequences than many existing forms of taxation, such as taxes on income or investment. Given that a reduction in carbon emissions will go hand-in-hand with more sustainable agricultural and forestry practices, lower levels of fossil fuel extraction and combustion and reduced reliance on politically volatile regions, a lot of good could come from the incentive to innovate a carbon tax would create. There will be losers, such as those invested in the Alberta oil patch, but frankly anything that slows that utter raping of northern Alberta is probably a good thing.
I think the problem with your argument is that assumption that measures taken to reduce GHG emissions will be exceedingly detrimental to the economy. A gradually introduced, predictable (and preferably global) carbon tax need not be economically detrimental, and could indeed have fewer negative economic consequences than many existing forms of taxation, such as taxes on income or investment. Given that a reduction in carbon emissions will go hand-in-hand with more sustainable agricultural and forestry practices, lower levels of fossil fuel extraction and combustion and reduced reliance on politically volatile regions, a lot of good could come from the incentive to innovate a carbon tax would create. There will be losers, such as those invested in the Alberta oil patch, but frankly anything that slows that utter raping of northern Alberta is probably a good thing.