How are Hansen's Global Warming predictions panning out?

Despite your coy posting, you want us to look at a year and compare it to another year. Ie, compare the red dots.

Sorry, it just doesn't work that way. As I've posted here in the past, you need to average a lot of years to be able to say whether a trend in global temperature is or is not statistically significantly different from zero, because there are large annual temperature changes due to "weather" (meaning, all kinds of short-term phenomena).

Realclimate makes this point pretty clearly, and those guys actually run models for a living, so they ought to know the underlying statistics. Here's their discussion of "short term trends".

RealClimate

Here's their analysis of Hansen's two-decade-old projections, with a lot of technical detail.

RealClimate

In both pieces, they make it clear that it's nonsensical to compare individual years. Why? Because the random variation due to weather is very large compared to any systematic trend due to global warming. Because you are looking at noise if you look at individual years.

Exactly how nonsensical is it, to look at any one year? Well, how large is the annual variation in weather compared to the annual projected warming trend? That is, how much are you confusing weather with climate, if you look at individual years?

The answer is, almost all of of the year-to-year fluctuation is weather. So that if you focus on individual years, you are (almost entirely) talking about weather, not climate.

Let's put some numbers on that. The middle-range scenario in Hansen's projections (the one that most closely matches the C02 forcings that actually occurred) projected warming of something under 0.25 degrees centigrade per decade. That's an average annual impact of 0.025 degrees per year. Now, look at the graph, and see that the typical annual variation in global temperature is easily 10x larger than that. That's why you can't look at individual years and say much of anything. If you look at any one year, you are looking at weather, not climate.

If you want to start looking at climate, average the years to get rid of the transient weather component. If Hansen's prediction were in the ballpark, you'd see the average datapoint on the left side of your graphs falling just below the zero line, and the average datapoint on the right side of your graphs falling just above the line. I'm not going to take the time to plot them, but that sure looks about right to me. The average of the temperature datapoints, as shown in the graphs, appear reasonably close to what Hansen projected.

If it stays cool, sure, I'll change my mind. Given that the current La Nina appears to be breaking up now, and that we're starting a new solar cycle as of this spring, it seems unlikely that global temperatures will stay low. But facts are facts. If the facts change I will change my mind. But it's just nonsense to look at individual years.

So, my conclusion, based on averaging the datapoints by eye, is that Hansen was in the ballpark. But you don't have to take my work for it, you can read what the experts in climate have said, as in the realclimate analysis above.

 

Tim, give it up. Nobody cares.

 

Looks to me that in all graphs the trend is to be in the upside. It may go up and down but compare how many of the points are over the 0 line after 2000 in comparison to previous dates.

Besides this is the real comparison:

 

Hansen thinks oil companies should be sued just like the Tobacco Companies for not only failing to do anything to mitigate climate change they were contributing to but going beyond failing to inform to actively covering up the damage they were doing.

"James Hansen, one of the world's leading climate scientists, will today call for the chief executives of large fossil fuel companies to be put on trial for high crimes against humanity and nature, accusing them of actively spreading doubt about global warming in the same way that tobacco companies blurred the links between smoking and cancer."

"Speaking before Congress again, he will accuse the chief executive officers of companies such as ExxonMobil and Peabody Energy of being fully aware of the disinformation about climate change they are spreading."

He'll also be campaigning to unseat members of Congress that have obstructed legislation on climate change and colluded with big oil.

 

I think he's spot on.

 

I disagree with this POV because it implies that the users are blameless victims, which is a load of shite. The blame falls squarely on us. Granted, the oil companies have been working hard (some harder than others) to spin things to their advantage, but the end user accepts a large part of the blame for the problem. Granted, we don't have a lot of alternative choices, but who's fault is that? Who has willingly gone along with the short term view and purchased loads of cheap, dirty fuel. Who stuck it to Carter for taking the long view back in the '70's? The problem lies in the fact that the vast majority of people would rather spend a dime now and $50 later as opposed to $1 now and a $1 later.

 

I'm not saying the users are blameless.

But there should be some culpability for intentionally disseminating false information to cover up the increasing climate change and the fact that oil and gas use is hugely contributing to it.

Would we even be arguing about whether humans contributed to climate change or to what extent if it wasn't for the oil companies smoke and mirrors campaign? Shouldn't they pay for their part in a massive cover up? This does mirror the Tobacco companies who KNEW of both the dangers of smoking and the addictiveness and not only covered up but denied under oath.

 

It is a matter of degree. Cigarette manufacturers deceived consumers by increasing the bioavailability of tobacco. In effect, the concentration of tobacco in the cigarette remained the same while more of it went into people's lungs. They also knew about the carcinogenic effects of cigarette smoke.

Although climate change due to greenhouse gases was a clear possibility only relatively recently has it gone beyond speculation to empirical observation.

Both cigarette makers and oil companies are responsible for manufacturing misinformation after the ill effects of their products were proven. Consider, people STILL smoke.

Not trying to defend oil companies. They are clear murderers because of their involvement in the Iraq and other wars. But that's another story.

 

Substitute people still smoking with the damage the increase in the price of gas is causing. We could have been conserving and developing alternative technologies years ago.

Oil and the Big 3 conspired to limit CAFE, dismantle the CA electric car legislation, etc.

And considering the harm to the economy and the air everyone breaths....it goes way beyond "second hand smoke". "Non-smokers" are being harmed by their decades of obstruction and deceit.

Same tune different lyrics.

 

Psst Tim. If you increase the scale of the vertical axis and make the dots brighter and make the line fainter it will make your position look even stronger.

 

What were his explicit predictions? I see the chart, but I do not know his predictions.

 

Follow the link to the realclimate.org analysis and chart.

 

Thanks! I wish I could say the same about you.

 

I did, but I was looking for something that overlayed Hansen's predictions normalized to the OP's chart. When dealing with climate models, an comparision between one group's data and another group's model requires quite a degree of intellectual integrity, otherwise a comparision is more of a Rorschach Test than a learning experience.

 

His mid-level scenario predicted warming at an average of 0.24 degrees centigrade per decade.

So, take a decade on the left half of the chart and average the heights of the data point, and plot that at the mid-point of the decade. (By eye, I mean.) Then do the same for a decade on the right. Those two mid-points are 10 years apart. Based on Hansen's projections, the more recent decade average should be about 0.24 degrees centigrade higher than the previous decade average.

Or, as I said above, the points on the left should average to just below the line, the points on the right should average to just above the line. Which is how it looks to me.

That's the proper way to evaluate this by eye, not the incorrect 0.5 degrees as posted above, and certainly not by looking at the start year and end year in isolation.

 

Thanks Tim, I see an upward trend which confirms the many environmental scientists theory that the earth's atmosphere is warming.
Now what will we do to curb the trend?

 

Hey. Doesn't God worry about all this stuff? Just kidding--I think.