Time Magazine Compares Iwo Jima to Global Warming

[JeffXD]

Originally Posted by jdavionic

Did they say we needed to attack the same problem on Mars too?

I think I mentioned it before, The Mars Rovers run on unleaded gasoline and that right there is enough to causing warming of the planet.

[Etta Place]

On Earth, we have poles melting, surface temperature rising, tropospheric temperatures rising, permafrost melting, glaciers worldwide melting, CO2 concentrations increasing, borehole analysis showing warming, sea ice receding, proxy reconstructions showing warming, sea level rising, sea surface temperatures rising, energy imbalance, ice sheets melting, and stratospheric cooling, all of which leads us to believe the earth is undergoing global warming driven by an enhanced greenhouse effect.

One Mars we have one spot melting, which leads us to believe that ... one spot is melting.

From Grist answers to skeptics.

[FrankRizzoXD40]

Originally Posted by Etta Place

From Grist answers to skeptics.

Several of those things can't apply to Mars., so that point is irrelevant.

For example, Mars is warming, but the sea levels can't rise because Mars doesn't have any oceans.

Frank

[Etta Place]

Originally Posted by FrankRizzoXD40

Several of those things can't apply to Mars., so that point is irrelevant.

For example, Mars is warming, but the sea levels can't rise because Mars doesn't have any oceans.

Frank

From realclimate.org:

So what is causing Martian climate change now? Mars has a relatively well studied climate, going back to measurements made by Viking, and continued with the current series of orbiters, such as the Mars Global Surveyor. Complementing the measurements, NASA has a Mars General Circulation Model (GCM) based at NASA Ames. (NB. There is a good "general reader" review of modeling the Martian atmosphere by Stephen R Lewis in Astronomy and Geophysics, volume 44 issue 4. pages 6-14.)

Globally, the mean temperature of the Martian atmosphere is particularly sensitive to the strength and duration of hemispheric dust storms, (see for example here and here). Large scale dust storms change the atmospheric opacity and convection; as always when comparing mean temperatures, the altitude at which the measurement is made matters, but to the extent it is sensible to speak of a mean temperature for Mars, the evidence is for significant cooling from the 1970's, when Viking made measurements, compared to current temperatures. However, this is essentially due to large scale dust storms that were common back then, compared to a lower level of storminess now. The mean temperature on Mars, averaged over the Martian year can change by many degrees from year to year, depending on how active large scale dust storms are.

In 2001, Malin et al published a short article in Science (subscription required) discussing MGS data showing a rapid shrinkage of the South Polar Cap. Recently, the MGS team had a press release discussing more recent data showing the trend had continued. MGS 2001 press release MGS 2005 press release. The shrinkage of the Martian South Polar Cap is almost certainly a regional climate change, and is not any indication of global warming trends in the Martian atmosphere. Colaprete et al in Nature 2005 (subscription required) showed, using the Mars GCM, that the south polar climate is unstable due to the peculiar topography near the pole, and the current configuration is on the instability border; we therefore expect to see rapid changes in ice cover as the regional climate transits between the unstable states.

Thus inferring global warming from a 3 Martian year regional trend is unwarranted. The observed regional changes in south polar ice cover are almost certainly due to a regional climate transition, not a global phenomenon, and are demonstrably unrelated to external forcing. There is a slight irony in people rushing to claim that the glacier changes on Mars are a sure sign of global warming, while not being swayed by the much more persuasive analogous phenomena here on Earth…

[Palmguy]

Originally Posted by Etta Place

From realclimate.org:

Thus inferring global warming from a 3 Martian year regional trend is unwarranted.

My take: Thus inferring global warming from even a 100 year trend on a planet that is supposedly billions of years old is unwarranted.

[FrankRizzoXD40]

Originally Posted by Palmguy

My take: Thus inferring global warming from even a 100 year trend on a planet that is supposedly billions of years old is unwarranted.

Smart observation.

Frank

[Etta Place]

Originally Posted by Palmguy

My take: Thus inferring global warming from even a 100 year trend on a planet that is supposedly billions of years old is unwarranted.

Answer: The reliable instrumental record only goes back 150 years in the CRU analysis, 125 in the NASA analysis. This is a simple fact that we are stuck with. 2005 was the warmest year recorded in that period according to NASA, a very close second according to CRU. Because of this limit, it is not enough to say today that these are the warmest years since 150 years ago, rather one should say 'at least':
1998 and 2005 are the warmest two years in at least the last 150.

But there is another direct measurement record available that can tell us things about temperature over the last 500 years, and that is borehole measurements. This involves drilling a deep hole and measuring the temperature of the earth at various depths. It gives us information about century-scale temperature trends, as warmer or cooler pulses from long term surface changes propagate down through the crust.
Using this method we can see that temperatures have not been consistently this high as far back as this method allows us to look. This way of inferring surface temperatures does smooth out yearly fluctuations and even short term trends, so we can not know anything directly about individual years. But given the observable range of inter-annual variations recorded over the last century, it is quite reasonable to rule out single years or even decades being far enough above the baseline to rival today.

Using this record, we can reasonably conclude that it is warmer now than any time in at least the last 500 years.
It is possible to make reconstructions of temperature much further back, using what are called proxy data. These include things like tree rings, ocean sediment, coral growth, layers in stalagmites, and others. The reconstructions available are all slightly different and provide sometimes more and sometimes less global versus regional coverage over the last one or two thousand years. Note: this covers what is often referred to as the Medieval Warm Period. As noted, all these reconstructions are different, but ...

... they all show some similar patterns of temperature change over the last several centuries. Most striking is the fact that each record reveals that the 20th century is the warmest of the entire record, and that warming was most dramatic after 1920.

Thus, we can reasonably say it is warmer now than any other time in at least the last 1,000 years.

The only other candidate for a higher temperature period -- going back through the entire Holocene (~10,000bp to now) -- is called the Holocene Climatic Optimum some 6,000 years ago. It is not known exactly what the temperatures were then; the farther back in time we try to look, the greater the uncertainties. Even so, the Holocene Climatic Optimum has long been cautiously thought to be almost as warm or even warmer than now.
That conclusion is starting to look less likely, as it has been determined that the anomalous warmth of that time was actually confined to the northern hemisphere and occurred only in the summer months.

Robert Rohde's website, Global Warming Art, has a nice graph of many reconstructions of Holocene temperature, regional and global, all super-imposed with an average of all of them combined, shown below. This represents the best estimate available of global temperatures in the Holocene.
Thus, we can reasonably believe it is warmer now than at any other time in at least the last 10,000 years.
Before the current interglacial, the planet was in the grip of a much colder glacial period with ice sheets well down into the continental U.S. This period ended just some 11,000 years ago. The record of glacial-interglacial cycles can be read in Antarctic ice core analysis, and it shows these cycles over many 100Kyr periods. The IPCC offers a good version of this graph.
If our reading of the Holocene is correct, it is warmer now than at any other time in over the last 100,000 years.

And that is a bit more than 100 years. It is, in fact, the entire history of our species.

'One hundred years is not enough' | Gristmill: The environmental news blog | Grist

[FrankRizzoXD40]

Originally Posted by Etta Place

...

What do you have to say about those graphs?

I tried quoting you but there is nothing to quote...

Frank

[Etta Place]

Originally Posted by FrankRizzoXD40

What do you have to say about those graphs?

I tried quoting you but there is nothing to quote...

Frank

I am not a scientist. I have referred to the websites where they refute the objections of global warming skeptics, like some of the people on this website, and apparently no one is reading the information there. So, I am merely posting the evidence here that disputes the skeptics - like those who say 100 years of data is insufficient.

[jmichna]

Etta,
Thank you for posting that data! I really mean it!!!

I assume you understand that the second and third graphs you posted use demonstrated flawed temperature data (e.g., the discredited and no longer accepted "hockey stick" model is your third chart) and that your fourth graph actually shows much higher temperatures at 8,000 years Before Present, and these temperatures remained higher than today through 1,000 years Before Present - way before any significant impact on the environment by Mankind. Your last chart shows the cyclical nature of climate change over the last 400,000 years, again before any possible intervention or impact by Man, and also shows - if you look carefully, that CO2 concentrations actually rise AFTER the temperature rises. All this is according to the data you posted.

Thanks again.