Are we reliving the 'global cooling scare' of the 1970s?

Hi AMP The whole ice-age scare of the 1970’s is something that really needs to be put into context. Both sides of the global warming debate often make the same mistakes when it comes to this issue. On the one side we have the skeptics claiming that scientists in the 70’s were wrong about global cooling 1 and on the other side are the believers who state that such a scare never happened.

Both sides are wrong. First off is the common mistake where it’s often claimed that there was significant cooling from c1945 to c1975. There wasn’t any significant cooling, what there was could perhaps be better described as a levelling off of temperatures.

Here’s a graph I compiled from all the major global temperature records http://www.flickr.com/photos/trevorandcl... it’s pretty consistent with the individual records – some show slightly more cooling, others show slightly less 2. It’s apparent from the graph that there had been a marked rise in temps preceding the ‘cooling’ period, especially from the turn of the 20th century, by mid century this rise levels off and doesn’t recommence for some 30 years. This levelling off was no great mystery and the scientists of the day quickly pointed out that a build up of gases in the atmosphere such as sulphur dioxide (SO2) were preventing sunlight from reaching Earth’s surface.

Unlike greenhouse gases such as carbon dioxide which retain heat in the atmosphere, SO2 has the opposite effect in that it effectively reflects incoming solar radiation back out into space, thus reducing the total amount of incoming solar radiation and reducing the availability of heat energy that could ultimately contribute to warming. Back then, in the mid 20th century, our industrial processes were emitting substantial amounts of SO2, most notably from power stations. As with the greenhouse gases of today, the amount of SO2 in the atmosphere was escalating and so an increasing amount of sunlight was being blocked.

This was compounded by the accumulation in the atmosphere of black particulate matter (BMP), this absorbs incoming solar radiation and again, reduces the amount of energy we receive from the Sun. The situation was further compounded by the accumulation of other aerosols in the atmosphere, this was providing the condensation nuclei upon which atmospheric water vapour was condensing and forming more clouds, most notably polar stratospherics. As with the SO2 and BMP, the clouds were reflecting and absorbing the heat energy from the Sun before it had a chance to reach us.

The scientists of the time correctly stated that if this issue wasn’t addressed and the amount of BPM, SO2 and other aerosols continued to increase as it had been doing, this would ultimately lead to a situation in which the global climate would cool down. This was music to the ears of the media who jumped on these findings and ran with stories of impending ice-ages and other global catastrophes – not at all representative of what the scientists were saying. In fact, the predictions were absolutely spot on and history has shown that the scientists were quite correct in their observations.

Indeed, had levels of the dimming pollutants in the atmosphere continued to rise unabated then the underlying warming trend could not only have been negated but could have been overwhelmed. It was an event in 1952 that was to trigger the cleaning up of the atmosphere and lead to a significant reduction in levels of SO2 and other pollutants. London was choking under a blanket of pollution and there were frequently days when the atmosphere over the city was heavily polluted.

In December of that year, calm anticyclonic conditions settled over the city bringing cold and foggy weather with them. These conditions prevented the dispersal of pollutants into the atmosphere and led to what has become known as the Great Smog (smog = smoke + fog). Conditions were so bad that more than 10,000 people died during the five days the smog lasted.

Personally, I find that the most knowledgeable deniers still tend to react to media's take on things. For some reason they don't like to listen to the scientists. The 'cooling' myth wasn't a myth at all.

The media's interpretation of what the scientists were trying to say *was* alarmist. Of course, somehow the deniers project that onto the scientists. Now of course you have some media hype about global warming and catastrophic sea level rise and Al Gore's movie and "The Day After Tomorrow".

That media interpretation of what the scientists are trying to say *is* alarmist. That's how they get ratings...and generate advertising revenues. Of course, somehow the deniers project that onto the scientists.

I personally don't have a problem with skeptics pointing out that some things are uncertain. But some of them seem outright delusional and discount what pretty much *every* scientist in the world is saying and that is, "the Earth is warming significantly." No, I didn't just say that they said that the warming for the past 15 years is statistically significant This includes skeptical scientists.

Skeptical scientists aren't sure about man's contribution to the warming, or the long-term, and so are conservative with their concern. Now deniers ignore what the scientists in the 70's were actually publishing and only pay attention to the media hype. Not surprising since they only listen to the media now and try to use the old to discredit the recent media hype.

Interestingly, though, they misinterpret and hype what the skeptical scientists are saying... If they were truly skeptics, they would cite scientific papers, not blogs, to make their case and stop complaining about scientists because of how the media interprets what the scientists say. If they want to be skeptical about something, they should start with being skeptical about the motives of "think" tanks and proven liars like Monkton.

I cant really gove you an answer,but what I can give you is a way to a solution, that is you have to find the anglde that you relate to or peaks your interest. A good paper is one that people get drawn into because it reaches them ln some way.As for me WW11 to me, I think of the holocaust and the effect it had on the survivors, their families and those who stood by and did nothing until it was too late.