Do you think that there is actually global warming or just another earth change coming on???

Question

Do you think that there is actually global warming or just another earth change coming on???

Answer 1

AGW...

Answer 2

I assume that you mean anthropogenic global warming, but why would it be only one or the other?  Surely the earth would not stop changing just because of some man-made changes being applied on top of the natural ones.

On the other hand, if the man-made changes are harmful, such as increasing the strenth and frequency of droughts, killing forests, increasing the range of tropical diseases, and harming the productivity of oceans through acidification, even if the man-made are not 100% of the problem, it makes sense for us to take some simple energy conservation measures to minimize the number of human deaths and reduce the economic damage that will result from our portion of the changes.

Unfortunately there is evidence that the natural trends at the moment are towards cooling:

"There is considerable evidence for solar influence on the Earth's pre-industrial climate and the Sun may well have been a factor in post-industrial climate change in the first half of the last century. Here we show that over the past 20 years, all the trends in the Sun that could have had an influence on the Earth's climate have been in the opposite direction to that required to explain the observed rise in global mean temperatures."

http://journals.royalsociety.org/content...

So the man-made influence towards warming may be greater than what we're actually observing, but the natural earth change is temporarily reducing our negative effects.  As the sun shifts into its natural warming cycle over the next couple of years, we'd better be making progress towards reducing greenhosue gases or we may see accelerated warming and the negative effects on water supply availability, food costs, and economies may come sooner than forecasted.

For example, here in the United States, Lake Mead, above Hoover Dam on the Colorado River, could be unusable within 6 years and the cost will be $2B/year for that one event alone:

http://news.nationalgeographic.com/news/...

There is a 50 percent chance Lake Mead will run dry by 2021 and a 10 percent chance it will run out of usable water by 2014...

"We were stunned at the magnitude of the problem and how fast it was coming at us," said marine physicist Tim Barnett.

"Make no mistake, this water problem is not a scientific abstraction but rather one that will impact each and every one of us that live in the Southwest," he said.

http://geochange.er.usgs.gov/sw/changes/...

"During the final, deepest years of the drought (years 17-22), costs to Upper Basin municipal and energy water uses were even larger. Total damages (including the non-consumptive uses) reach as high as $2 billion/year in the final years of the drought

http://www.nytimes.com/2007/10/21/magazi...

Steven Chu, a Nobel laureate and the director of the Lawrence Berkeley National Laboratory, one of the United States government’s pre-eminent research facilities, remarked that diminished supplies of fresh water might prove a far more serious problem than slowly rising seas.

Chu noted that even the most optimistic climate models for the second half of this century suggest that 30 to 70 percent of the snowpack will disappear. “There’s a two-thirds chance there will be a disaster,” Chu said, “and that’s in the best scenario.”

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So the argument that natural causes would let us off the hook is not a valid one.  If there are also man-made contributions that are having a harmful effect, we'd be stupid not to exercise some simple and profitable conservation efforts (Energy Star program and other power conservation, provide incentives for home solar, raise MPG standards), and to encourage all countries to do the same (particularly China and India).  

Here in the United States we have a long way to go to catch up with China's average 35 MPG.  I fully utilize the unique features of my current SUV, but the cost of hybrid SUVs delivering 35MPG would drop considerably if they were the standard model, manufactured in much higher quantities.

Answer 3

By global warming, I assume you mean human caused global warming.   The earth's climate changes constantly as every geologists knows.  Those that are surprised by changes are generally not geologists.  There is therefore a 50 / 50 chance of it warming or cooling.  It seems to be warming but the last few years might be the beginning of a cooling trend.  You have to specify a time interval.  For example, it may be cooling over the last 5 years, warming over the last 20 years, warming over the last 100 years, warming over the last 10,000 years, cooling over the last 5 million years, and dramatically cooling over the last 100 million years.  There is no reason to suspect that the latest warming isn't natural save for a slight influence that humans may have on it.  Human influence is almost certainly not enough to change the natural trends

Answer 4

The climate is always changing.  If it's not cooling, it's warming.

Change is natural, not man made, and completely natural.

There is no such thing as a static climate.

Answer 5

If you look at the North Pole throughout the ages you will notice that from time to time it changes its size and shape so I think that the reason the polar icecap is melting is so that the Pole can change once again, also you'll notice that the NP has shifted as well...my honest thoughts, natural occurence.

Yes I believe that cars etc do cause damage to the environment I don't believe it's on the scale that they're making us believe.

Answer 6

Of course there is global warming.  You can see it in this graph:

http://data.giss.nasa.gov/gistemp/graphs...

And it's not natural.  There are many basic scientific facts which can only be explained if the current global warming is being caused by an increased greenhouse effect due to carbon dioxide accumulating in the atmosphere from humans burning fossil fuels.

For example, the planet is warming as much or more during the night than day.  If the warming were due to the Sun, the planet should warm a lot more during the day when the Sun has influence.  Greenhouse gases trap heat all the time, so they warm the planet regardless of time of day.  Another example is that the upper atmosphere is cooling because the greenhouse gases trap the heat in the lower atmosphere.  If warming were due to the Sun, it would be warming all layers of the atmosphere.

http://answers.yahoo.com/question/index;...

We know it's warming, and we've measured how much:

http://www.epa.gov/climatechange/science...

Scientists have a good idea how the Sun and the Earth's natural cycles and volcanoes and all those natural effects change the global climate, so they've gone back and checked to see if they could be responsible for the current global warming.  What they found is:

Over the past 30 years, all solar effects on the global climate have been in the direction of (slight) cooling, not warming.  This is during a very rapid period of global warming.

http://news.bbc.co.uk/2/hi/uk_news/62902...

http://www.pubs.royalsoc.ac.uk/media/pro...

A recent study concluded:

“the range of  [Northern Hemisphere]-temperature reconstructions and natural forcing histories…constrain the natural contribution to 20th century warming to be <0.2°C [less than one-third of the total warming].  Anthropogenic forcing must account for the difference between a small natural temperature signal and the observed warming in the late 20th century.”

http://www.pnas.org/cgi/content/full/104...

You can see this in the third graph here, where the dotted lines are just from natural causes, and the full lines are natural + human causes:

http://www.pnas.org/content/vol104/issue...

If that’s not enough to convince you the Sun isn’t responsible, consider the fact that no scientific study has ever attributed more than one-third of the warming over the past 30 years to the Sun, and most attribute just 0-10% to the Sun.

http://answers.yahoo.com/question/index;...

So the Sun certainly isn't a large factor in the current warming.  They've also looked at natural cycles, and found that we should be in the middle of a cooling period right now.

"An often-cited 1980 study by Imbrie and Imbrie determined that 'Ignoring anthropogenic and other possible sources of variation acting at frequencies higher than one cycle per 19,000 years, this model predicts that the long-term cooling trend which began some 6,000 years ago will continue for the next 23,000 years.'"

http://en.wikipedia.org/wiki/Milankovitc...

http://www.sciencemag.org/cgi/content/ab...

So it's definitely not the Earth's natural cycles.  They looked at volcanoes, and found that

a) volcanoes cause more global cooling than warming, because the particles they emit block sunlight

b) humans emit over 150 times more CO2 than volcanoes annually

http://volcano.und.edu/vwdocs/Gases/man....

So it's certainly not due to volcanoes.  Then they looked at human greenhouse gas emissions.  We know how much atmospheric CO2 concentrations have increased over the past 50 years:

http://en.wikipedia.org/wiki/Image:Mauna...

And we know from isotope ratios that this increase is due entirely to human emissions from burning fossil fuels.  We know how much of a greenhouse effect these gases like carbon dioxide have, and the increase we've seen is enough to have caused almost all of the warming we've seen over the past 30 years (about 80-90%).  You can see a model of the various factors over the past century here:

http://en.wikipedia.org/wiki/Image:Clima...

This is enough evidence to convince almost all climate scientists that humans are the primary cause of the current global warming.

Answer 7

Unfortunately for the deniers, their theories keep getting disproved. It makes one wonder why someone posts disproved information to try to deny reality.

The solar output theory of reality deniers has been totally disproved. Increasing solar output cannot be the cause of global warming because... are you ready for this... solar output is decreasing. But does that stop the deniers from making their claims? Evidently not.

"IT HAS been one of the central claims of those who challenge the idea that human activities are to blame for global warming. The planet's climate has long fluctuated, say the climate skeptics, and current warming is just part of that natural cycle — the result of variation in the sun's output and not carbon dioxide emissions.

But a new analysis of data on the sun's output in the last 25 years of the 20th century has firmly put the notion to rest. The data shows that even though the sun's activity has been decreasing since 1985, global temperatures have continued to rise at an accelerating rate."