Have scientist been succesful in predicting the actual amout of global warming during the last centry?

Answer 1

scientists spent most of the last century preduicting global cooling. they are incompetent, as most scientists are. anyone who claims there is a consensus on global warming knows nothing of science. consensus has no bearing on science. every time there is a real scientific break through, the one man who finds out the truth spends decades being ridiculed by his peers. then he is finally proven right, and the others were all wrong. it is always this way, and it is this way with global warming. the globe may be warming, but we have nothing to do with it. the good thing is, that global warming is a good thing for people and animals. times of global cooling are when we have the worst droughts and famines

Answer 2

Well scientist not successfully as human can predict accurately but i am pretty sure that scientist can tell the actual amount of global warming by doing testing on the layer of snow in antarctia
they can predicte the about of global warming occured in the world.

Answer 3

Amancalledchuda,

You have made a mistake in your summation of the Deltoid/Hansen link.

That post of Tim Lambert's uncovers the fraud committed by a denialist. When you hover the mouse of the pic the temperature moves from the real position to the fake one created by a Climate Audit reader. Try reading the post, it is interesting. For anyone else, have a look at Real Climate's summary of Hansen's work which considers every factor required in making an honest assessment:

http://www.realclimate.org/index.php/archives/2007/05/hansens-1988-projections/

Answer 4

No, not really.

The best example of this is James Hansen’s guesses from back in 1988. So, how did he do?

Well, dana, in his answer here on this question, suggests Hansen did rather well, and, if you look at dana’s second link (this one… http://sciencepolicy.colorado.edu/prometheus/archives/climate_change/000836evaluating_jim_hanse.html ), it appears that he did.

But did he really?

Well, the graph that appears on dana’s webpage was created by none other than James Hansen himself – so we have to ask ourselves: do we believe it when Hansen provides his own proof that he was right? Well, what actually matters is comparing actual observed temperature (i.e. what temperature actually did) with what Hansen predicted, but the problem is there are different sources of observed temperature.

So which source did Hansen use? Well, if you check the webpage dana linked to, there’s a link in the paragraph below the graph that goes here… http://www.columbia.edu/~jeh1/hansen_re-crichton.pdf which is where the graph originally came from. It’s a paper by Hansen attempting to prove that he was right. If you scroll down to the bottom, there’s the graph again. Now read the caption under the graph and we find that the source for the observed temperature is “an update of the analysis of *Hansen* and Lebedeff…” So it’s Hansen’s own data! So he’s proving himself correct, by using his own temperature record!

The problem is, most other observed temperature sources show less cooling than Hansen’s GISS data set. This is interesting, because Global Warming Alarmists, such as dana, are constantly telling us that we should listen to the “consensus”. Why then does he quote a *minority* view on the observed temperature record?

So, what happens when we use a more “consensus” observed temperature data set? We get this… http://scienceblogs.com/deltoid/2006/08/climate_fraudit.php You can hover your mouse over the graph to move the observed temperature line out of the way and this reveals very clearly that it is following Hansen’s lowest, ‘Scenario C’ prediction.

So, observed temperature is following Hansen’s *lowest* guess.

But, it’s even worse than it seems, because Hansen’s three guesses weren’t simply high, medium and low; they predicted that we humans would do very different things with our Greenhouse Gas emissions.

So what did ‘Scenario C’ predict? Well, we can find this out from Hansen’s paper that I linked to above (here it is again… http://www.columbia.edu/~jeh1/hansen_re-crichton.pdf ) About halfway down the first page is a paragraph that starts “Scenario A was described as…”, but it’s not ‘Scenario A’ we’re after, it’s ‘Scenario C’, so keep reading and you’ll find that in ‘Scenario C’ Hansen predicted that “greenhouse gases were assumed to stop increasing after 2000.”

So ‘Scenario C’ assumed that CO2 (and the other greenhouse gasses) would stop rising after 2000, but, of course, they haven’t stopped rising at all. In fact, they are rising at least as fast as ever. Dana even posted a question recently that suggested they’re rising *much faster* than before.

But temperatures are rising as Hansen predicted they would if the rise in greenhouse gasses stopped seven years ago.

I would therefore argue that Hansen’s predictions were a little bit off the mark.

As ever with global warming - don't believe the hype.

Answer 5

polar ice cover is decreasing ...

sea level is rising ....

these symptoms are not unlike a 600 pound gorilla

bananas? ... check the data


Global warming is well known and established.

Latest findings like expected, in support (September 2006):

Carbon dioxide levels are substantially higher now than at any time in the last 800,000 years, the latest study of ice drilled out of Antarctica confirms.

The in-depth analysis of air bubbles trapped in a 3.2km-long core of frozen snow shows current greenhouse gas concentrations are unprecedented.

The East Antarctic core is the longest, deepest ice column yet extracted.

Project scientists say its contents indicate humans could be bringing about dangerous climate changes.

"My point would be that there's nothing in the ice core that gives us any cause for comfort," said Dr Eric Wolff from the British Antarctic Survey (BAS).

"There's nothing that suggests that the Earth will take care of the increase in carbon dioxide. The ice core suggests that the increase in carbon dioxide will definitely give us a climate change that will be dangerous," he told BBC News.
http://news.bbc.co.uk/1/hi/sci/tech/5314592.stm


Earth's surface has undergone unprecedented warming over the last century, particularly over the last two decades. Astonishingly, every single year since 1992 is in the current list of the 20 warmest years on record.

Answer 6

Yes, scientists have created models which fit the temperature data over the past century quite well:

http://en.wikipedia.org/wiki/Image:Climate_Change_Attribution.png

Also, in 1988 James Hansen predicted the global warming which has happened over the past 19 years quite accurately:

http://sciencepolicy.colorado.edu/prometheus/archives/climate_change/000836evaluating_jim_hanse.html

Answer 7

I'm sure they have. The current climate models are full of so many parameters that they can tune them to make any predictions they want. If can keep trying different combinations until they find one that matches, at which point they declare victory and claim their science is accurate.

Answer 8

Yes they have, but weren't these the same scientists a number of years ago that said mathematically bumbo bees can't fly. I believe they also said if anyone who traveled faster than the sound barrier would die.

Answer 9

Yes they have. The temperature of the climate has increased just 1.8degF in the last 100 years.

That's just a scant 0.018 deg/yr increase in just 100 years. And 100 years for the history of the Earth is just a blink of an eye.

Answer 10

Kind of. They don't "predict" what happened in the past. They explain why it happened. Here's a short version of the explanation.

http://www.globalwarmingart.com/wiki/Image:Climate_Change_Attribution.png