How does land use contribute to the effects of global warming?

AI Thread Summary
The discussion centers on the human contribution to climate change, with many participants expressing concern about anthropogenic greenhouse gas emissions as a significant factor in recent warming trends. There is a consensus that while climate change is a complex issue, the evidence points towards human activity as a major contributor, despite some skepticism about the reliability of climate experts. Participants highlight the potential catastrophic consequences of inaction, including severe impacts on ecosystems and human populations, particularly in vulnerable regions like Africa. The need for sustainable practices and changes in human behavior is emphasized as essential for mitigating climate change effects. Overall, the conversation reflects a strong inclination towards accepting scientific consensus on climate change while advocating for proactive measures to address it.

Assuming there is a global warming trend, how significant is the human contribution?

  • Totally fallacious. Complete fabrication. There is utterly no connection whatsoever.

    Votes: 0 0.0%
  • Human society has contributed in theory, but insignificant compared to natural trends.

    Votes: 8 26.7%
  • Our contributions will have measureable effects, but that's just the way it's going to be.

    Votes: 8 26.7%
  • We have created this problem, and only a massive change in human habit will avert disaster.

    Votes: 14 46.7%

  • Total voters
    30
Chi Meson
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This is the follow-up question.

Assuming that there is a warming trend, please give your opinion as to the human contribution to this trend. Once again, I would hope that the opinion is informed and not fanciful or political.

Sorry if none of these match your true opinion, but please choose the one closest to your stance, and qualify your responses here.
 
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I voted for the 4th option, with some trepidation. To explain my vote: disasters are very common as it is. By "disaster" I actually mean, a statistically significant increase in the number and scope of disasters as an effect of "fast" climate change. The wording might be misleading, since it immediatly suggests a sudden cataclycsm on a human time scale, rather than effects that have catastrophic consequences, both human (millions) and economic ($trillions), but which take decades of statistics before the correlation with anthropogenic CO2 is actually clear.

It's sort of funny that way - global climate is too big for any conscious human activity to control, and too slow for any single human to percieve.
 
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Climate change has divided many environmental scientists and well pretty much everyone else due to the media attention over the past couple of years. I've never looked at the evidence in detail nor do I come from a position where I could make an informed opinion about it. What I don't understand is that if experst in the field and a large number of them are concerened why do some people still persist in believing its a fabrication because essentially what they're doing is gambling on the fact that a large number of experts are wrong. Personally I don't like those odds.

We really have two choices; change our habits which really doesn't harm us at all, just an inconvenience or gamble on the fact that the evidence has been misinterpreted at the potential cost of millions of human and animal and plant lives and potential destruction of thousands of species forever.

I know which I consider the more logical option.
 
Even if Global Warming wasn't a problem, the same measures that we are taking to curb GW should be taken anyway, to improve the quality of life for people in all the world's cities and towns,
 
Most climage experts seem to think that we are at least partly responsible. Beyond that, it shouldn't be a matter of opinion for amateurs.

No vote; no applicable option. To me this would be a bit like voting on String Theory. Unless you're an expert, what good is your opinion?
 
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Ivan Seeking said:
Most climage experts seem to think that we are at least partly responsible. Beyond that, it shouldn't be a matter of opinion for amateurs.

No vote; no applicable option.
Good call. If a solution to GW is agreed upon by a group of experts, the government should allow them to go ahead and implement it without a public. We shouldn't allow the common person to have a say, since many will likely be in denial / uninformed.
 
Experts tells us the facts, but it is our responsibility to take action.
 
There is way too much hype, fearmongering, politicalization, press sensationalization, limelight desire, economics, etc to form an neutral opinion.

Better to study the physics of EM-radiation, adsorption and the statistics of multiproxy reconstructions and the selectivity of evidence.
 
My opinion is that enhanced greenhouse effect is the best current explanation as a significant factor to explain the recent temperature trends. Other explanations, such as a strong solar cause, or GCRs, are not well ironed out and seem to have more problems.

There is the possibility that recent warming is due to an unknown cause not yet discovered, but until then I have to go for enhanced greenhouse effect as most likely.
 
  • #10
In my opinion, the weirdest thing about these two polls is their order is more or less reversed. Everyone seems more strongly convinced global warming is anthropogenic than they are that it is severe.

I would say just the opposite: I think the case that it is occurring, and could be quite pronounced, is much stronger than the relatively weak case that it is primarily anthropogenic.

Imagine the Elizabethan Little Ice Age in today's society. It would cause much greater upheaval in terms of trade patterns and whatnot than it did back in Shakespeare's day. Of course, people have a lot more resources at their disposal, but they consume a great deal more resources in order to maintain their expected standard of living.
 
  • #11
"Climate experts" are not to be trusted. If they didn't spout doomsday predictions, they'd be jobless.
 
  • #12
durt said:
"Climate experts" are not to be trusted. If they didn't spout doomsday predictions, they'd be jobless.

A bit like counter terrorism experts
 
  • #13
I am not a climatologist, but I have spent a good amount of effort to learn about global warming. I have looked at both sides of the controversy and what I have found is that there is a lot we do not know.

IN my research I have also discovered a lot of misinformation on the subject, most of it coming from political think tanks.

I chose number four.

The bottom line is this;

Green house gases are the only forcings in climate models that match the record. The increase in GHG is anthropogenic. Unless there is a major discovery of some other forcing, (highly unlikely) the current warming is anthropogenic.

Will it be a problem?

Look at Africa. It already is.

BOULDER- The percentage of Earth's land area stricken by serious drought more than doubled from the 1970s to the early 2000s, according to a new analysis by scientists at the National Center for Atmospheric Research (NCAR). Widespread drying occurred over much of Europe and Asia, Canada, western and southern Africa, and eastern Australia. Rising global temperatures appear to be a major factor, says NCAR's Aiguo Dai, lead author of the study.
http://www.ucar.edu/news/releases/2005/drought_research.shtml

Africa could be faced with 25% less water by the end of the century because of global warming, scientists have warned in a new report

http://news.bbc.co.uk/2/hi/science/nature/4769978.stm

Africa is being hit the hardest, while they contribute the fewest GHG's. It just doesn't seem fair to me.
 
  • #14
Couperin said:
Even if Global Warming wasn't a problem, the same measures that we are taking to curb GW should be taken anyway, to improve the quality of life for people in all the world's cities and towns,

Excellent point.

Sustainability is the mantra for the 21st century. Let's leave the 22nd century's people an ecologically sustainable economy!
 
  • #15
I'm not sure I have a very well defined idea of what sustainability is what exactly does it mean?
 
  • #16
Mk said:
I'm not sure I have a very well defined idea of what sustainability is what exactly does it mean?

It means that our great grand children and their great grand chjldren will inherit an inhabitable world.
 
  • #17
Given a choice of:

Our contributions will have measureable effects, but that's just the way it's going to be.

We have created this problem, and only a massive change in human habit will avert disaster.


I would prefer an option - Our contributions will have measureable effects, but we can make changes to mitigate the situation and develop a sustainable future. Perhaps a massive change in attitude or thinking is required.

Certainly a situation where the US with ~5% of the world's population consumes 26% of the energy resources is unsustainable, especially another substantial portion of the world's population is determined to achieve the same level of consumption.

Renewable resources of energy and otherwise, and more efficient methods of utilization, must be developed. Harmful practices must be eliminated - e.g. deforestation, excessive use of fertilizers, . . . .

Actions like reforestation must be implemented on a global scale.
 
  • #18
Skyhunter said:
Green house gases are the only forcings in climate models that match the record.
Maybe it isn't being "forced". Was the Little Ice Age "forced"? Was the Climactic Optimum "forced"? I also don't think the models match anything well, but that point is one widely debated elsewhere. I hate going over retreads all the time.

But consider for a moment that the bulk of the past 1,000 years, where we have fiarly good records and no real CO2 emmisions hasn't been "forced".

Skyhunter said:
Look at Africa. It already is.<snipped section on drought>
The drought claim has always puzzled me greatly, and as far as I know, runs contrary to most climate models. Water certainly evaporates more as you add more heat. But it is a closed system. Where is the evaporated water supposed to go? It comes back as rain. More heat means more rain. Since some 75% of the Earth's surface was covered by water the lst time I looked, increased evaporation from the land masses shoudl be more than offset by increased evaporation (and subsequent rainfall) from the oceans.

The wind patterns will change in some areas, and that will affect the rainfall each region will receive. But on average, the rainfall should go up, not down. And wind pattern changes are notoriously unpredictable. It's what they invented the term "butterfly effect" for.

I'm willing to accept some of the "global" conclusions, but whenever climatologists start making specific predictions, you need to need to go into the salt business.
 
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  • #19
twisting_edge said:
The drought claim has always puzzled me greatly, and as far as I know, runs contrary to most climate models. Water certainly evaporates more as you add more heat. But it is a closed system. Where is the evaporated water supposed to go? It comes back as rain. More heat means more rain. Since some 75% of the Earth's surface was covered by water the lst time I looked, increased evaporation from the land masses shoudl be more than offset by increased evaporation (and subsequent rainfall) from the oceans.
More heat doesn't necessarily mean more rain (although part of the problem is getting the rain on a regular basis, rather than having a dry spell followed by torrential rains). The southern and eastern parts of Africa are having significant drought problems, such that the food production has decreased. Australia is having their worst drought (in the third year) ever recorded. Most of the biggest wheat producing areas around the world are seeing dramatic reductions in production - due to reduced rainfall or drought!

Drought means - it's not raining or it's not raining sufficiently.

Drought intensifies over eastern and southern Australia as spring rains fail
http://www.bom.gov.au/climate/drought/drought.shtml

Droughts & Flooding Rain
http://www.abc.net.au/science/scribblygum/august2006/

Droughts & Flooding Rain
http://www.guardian.co.uk/australia/story/0,,1941942,00.html

http://en.wikipedia.org/wiki/2006_Horn_of_Africa_food_crisis
http://www.dfid.gov.uk/News/files/horn-drought-2006.asp

Africa: Weather hazards assessment 19 - 25 Oct 2006
http://www.reliefweb.int/rw/rwb.nsf/db900SID/LZEG-6UPQ9W?OpenDocument
http://earthobservatory.nasa.gov/NaturalHazards/shownh.php3?img_id=13329

In the US - http://www.drought.unl.edu/dm/monitor.html

But - some areas are getting too much rain

Floods in East Africa
http://earthobservatory.nasa.gov/NaturalHazards/shownh.php3?img_id=13958

Floods ravage Horn of Africa
http://www.abc.net.au/news/newsitems/200611/s1791983.htm

Guinea: Floods
http://www.reliefweb.int/rw/RWB.NSF/db900SID/JOPA-6U7BJ7?OpenDocument

================================================
Some references from http://www.ocean.washington.edu/courses/oc588/

IPCC (2001) Climate Change 2001: the scientific basis, Contribution of Working Group I in the Third Assessment Report of the Intergovernmental Panel on Climate Change (Houghton et al., eds.), Cambridge University Press, Cambridge, U.K. and New York, NY, USA, 881 pp.

Toggweiller, R. and J. Sarmiento (1985) Glacial to interglacial changes in atmospheric carbon dioxide: The critical role of ocean surface water at high latitudes, in: The Carbon Cycle and Atmospheric CO2: Natural variations Archean to Present, (Sundquist, E. and Broecker, W. S., eds) A.G.U. Geophysical Monograph 32, Wash. D. C.

Sabine, C.L., et al., The oceanic sink for anthropogenic CO2, Science, 305, 367-371, 2004.

Takahashi, T., The fate of industrial carbon dioxide, Science, 305, 352-353, 2004.

Quay, P., et al., Carbon isotopic composition of atmospheric CH4: Fossil and biomass burning source strengths, Global Biogeochemical Cycles, 5, 25-47, 1991.

Long, S.P., E.A. Ainsworth, A. Rogers, and D.R. Ort, Rising atmospheric carbon dioxide: Plants FACE the Future, Annu. Rev. Plant Biol., 55, 591-628, 2004.

C. Korner, Through enhanced tree dynamics carbon dioxide enrichment may cause tropical forests to lose carbon, Phil. Trans. R. Soc. Lond. B, 359, 493-498, 2004.
 
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  • #20
Mk said:
I'm not sure I have a very well defined idea of what sustainability is what exactly does it mean?

Here are some definitions.

google said:
Definitions of Sustainability on the Web:

The ability to provide for the needs of the world's current population without damaging the ability of future generations to provide for themselves. When a process is sustainable, it can be carried out over and over without negative environmental effects or impossibly high costs to anyone involved.
www.sustainabletable.org/intro/dictionary/

Meeting the needs of the present without compromising the ability of future generations to meet their own needs.

www.afsc.org/trade-matters/learn-about/glossary.htm[/URL]

The ability of an ecosystem to maintain ecological processes and functions, biological diversity, and productivity over time.
[url]www.umpqua-watersheds.org/glossary/gloss_s.html[/url]

Sustainable development The concept of meeting the needs of the present without compromising the ability of future generations to meet their needs. The terms originally applied to natural resource situations, where the long term was the focus. Today, it applies to many disciplines, including economic development, environment, food production, energy, and social organization. Basically, sustainability/sustainable development refers to doing something with the long term in mind. ...
[url]www.dantes.info/Projectinformation/Glossary/Glossary.html[/url]

A characteristic of a process or state that can be maintained indefinitely .
[PLAIN]www.jsdnp.org.jm/glossary.html[/URL]

As defined by the US EPA, sustainability refers to the ability of an ecosystem to maintain a defined/desired state of ecological integrity over time.
[PLAIN]www.parks.ci.portland.or.us/IPM/ipm_glossary.htm[/URL]

An architectural property of a program which allows continued viability.
web.mit.edu/oki/learn/gloss.html

Economic development that takes full account of the environmental consequences of economic activity and is based on the use of resources that can be replaced or renewed and therefore are not depleted.
biology.usgs.gov/s+t/SNT/noframe/zy198.htm

Meeting present needs without preventing future generations from meeting their needs.
[PLAIN]www.scottish-enterprise.com/sedotcom_home/help/help-glossary.htm[/URL]

To keep in existence; maintain. To supply with necessities or nourishment; provide for earth
[url]www.planetpals.com/ecodictionary.html[/url]

The degree to which flood and coastal defence solutions avoid tying future generations into flexible and/or expensive options for defence. This will usually include consideration of inter-relationships with other defences and likely developments and processes within a catchment or coastal cell.
[PLAIN]www.essex-estuaries.co.uk/glossary.htm[/URL]

The use of ecosystems and their resources in a manner that satisfies current needs while allowing them to persist in the long term.
research.amnh.org/biodiversity/symposia/archives/seascapes/glossary.html

The measure by which a human activity can be continued without relying upon limited resources, such as fossil fuels, or by leaving waste behind, and also giving nature the chance to replenish itself.
[PLAIN]www.ecohealth101.org/glossary.html[/URL]

the exploration, design, construction, operation and closure of mines in a manner that respects and responds to the social, environmental and economic needs of present generations and anticipates those of future generations in the communities and countries where we work.
[PLAIN]www.placerdome.com/educentre/glossary.html[/URL]

There are many definitions of sustainability, but a good one for the HSE-MIS context is:
[PLAIN]www.hsewebdepot.org/imstool/GEMI.nsf/WEBDocs/Glossary[/URL]

To keep in existence, to maintain or prolong
[PLAIN]www.ifdn.com/teacher/glossary.htm[/URL]

Sustainability is effectively the goal of sustainable development. It is the ideal end state which we must aspire.
[url]www.esd.rgs.org/glossarypopup.html[/url]

Sustainable development is the process of conducting business and commerce in a resource conservative and resource efficient manner such that operations do not compromise the ability of future generations to meet their own needs. The essential elements of this trend are the promotion and maintenance of business and community development strategies that lead to a better business environment in the future; one sustained by stable, healthful communities within a clean, safe environment. ...
[PLAIN]www.mass.gov/epp/info/define.htm[/URL]

Use of resources in a manner that allows the resources to be replenished by natural systems, as well avoidance of pollution that damages biological systems. Use of resources in such a manner that they will never be exhausted.
web-savvy.com/river/Schuylkill/glossary.html

the ability of natural resources to provide ecological, economic, and social benefits for present and future generations.
[PLAIN]https://www.uwsp.edu/natres/nres743/Glossary.htm

(Durabilité)
www.unesco.org/ios/eng/evaluation/tools/outil_02e.htm

creating new ways to live and prosper while ensuring an equitable, healthy future for all people and the planet (Natural Step website).
www.epa.qld.gov.au/environmental_management/sustainability/industry/sustainability_roadmap/glossary/[/URL]

The ability to continue an activity for a long period of time while maintaining diverse, healthy and productive ecosystems.
[PLAIN]www.pce.govt.nz/reports/pce_reports_glossary.shtml[/URL]

of a fishery must be defined in terms of goals within four separate categories. Together, these science and policy components interact transparently to form a dynamic and adaptive process:
map.mapwise.com/safmc/LinkClick.aspx

A concept and strategy by which communities seek economic development approaches that benefit the local environment and quality of life. Sustainable development provides a framework under which communities can use resources efficiently, create efficient infrastructures, protect and enhance the quality of life, and create new businesses to strengthen their economies. ...
[url]www.ci.austin.tx.us/zoning/glossary.htm[/url]

the property of being sustainable
wordnet.princeton.edu/perl/webwn

Sustainability is an economic, social, and environmental concept. It is intended to be a means of configuring civilization and human activity so that society and its members are able to meet their needs and express their greatest potential in the present, while preserving biodiversity and natural ecosystems, and planning and acting for the ability to maintain these ideals indefinitely. Sustainability affects every level of organization, from the local neighborhood to the entire planet. ...
en.wikipedia.org/wiki/Sustainability[/QUOTE]

Here are some examples.

I am vegan, but if I did eat animals I would agree with Joel Salatin about most things. He has turned an infertile, overworked and depleted tenant farm, into a productive and fertile family farm.

[url]http://www.polyfacefarms.com/[/url]

Here is what I consider the key to sustainability; [B]investing in social capital.[/B]

[PLAIN]http://www.americancity.org/article.php?id_article=64

http://www.cityrepair.org/index.html

By empowering citizens to take back the commons, people begin to experience the shared consequences of decisions made by people outside of their community. These decision makers are heavily influenced by special interests. Interests so deeply imbedded in our culture and society that we accept them as natural.

My personal passion ATM is urban watersheds. Living roofs are an excellent way to improve the environmental quality of cities. Daylighting and restoring natural creeks within the cities, and planting extensive living roofs can improve the water and air quality, while reducing the UHI effect.

Here is a good introductory to living roofs.

http://www.greenroofs.com/Greenroofs101/index.html

Extensive living roofs are easier and cost effective in most applications. I am more interested in intensive living roofs, edible roofs in particular.
 
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  • #21
Astronuc said:
More heat doesn't necessarily mean more rain (although part of the problem is getting the rain on a regular basis, rather than having a dry spell followed by torrential rains). The southern and eastern parts of Africa are having significant drought problems, such that the food production has decreased. Australia is having their worst drought (in the third year) ever recorded. Most of the biggest wheat producing areas around the world are seeing dramatic reductions in production - due to reduced rainfall or drought!
Fine. Now relate that back to global warming.

It's not hard to establish that connection: the changing weather patterns means the ideal places to grow crops are going to move around. But it is not the warming per se that is causing the problem, it's the change in the weather patterns, something I think has been around for a long, long time.
 
  • #22
twisting_edge said:
Fine. Now relate that back to global warming.

It's not hard to establish that connection: the changing weather patterns means the ideal places to grow crops are going to move around. But it is not the warming per se that is causing the problem, it's the change in the weather patterns, something I think has been around for a long, long time.
Certainly weather patterns change and have been for eons. But are the weather patterns changing in ways they have not for thousands of years? Or are the droughts/floods being exacerbated by global warming?

I prefer to be 'conservative' or cautious, because if human activity is a factor, we have to change that. And it won't cost a lot, but in fact more efficient use of resources will reduce the cost and ensure a sustainable quality of life.

I do think there is a lot of hype by both proponents and opponents of anthropocentric causes of global warming.
 
  • #23
One of the major problems with warming is that evaporation over land is increased. The land dries faster. Land use is becoming a huge factor. With increased deforestation, and the destruction of watersheds through unsustainable development, water will become more valuable than oil in the future.

http://www.earth-policy.org/Books/PB2/pb2ch5.pdf is an excellent chapter entitled "Natural Sytems Under Stress".
 
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