Note: possibly obvious, but you never know: I'm not posting this
because I think you can learn any useful science from it. Its
totally out of date. Read the
The November 1976 edition has a story about climate. Its the lead story but didn't make the cover - Robert Redford on the outlaw trail was more sexy in his cowboy hat. Plus ca change...
I would summarise the Nat Geog article as supporting my POV: its non-commital. You could easily find out-of-context quotes to support your own POV, and so could I. So I'll do my best to quote honestly. The Nat Geog stuff is pretty similar to the Newsweek article from about the same time but much longer, and probbaly better.
To begin I'll show you the last two pages of the article and the graph thereon. Click on the thumbnail for a larger version (1200x900). Despite my poor photo (sorry about the flash; apologies about the appalling state of our carpet) I'm sure you can see the graph at the top with two dotted continuations at the end, one marked "warmer", the other "cooler". This is a pretty fair summary: no prediction (other than change, I suppose) and a clear indication of uncertainty.
Comments on this page: see at the bottom.
So now, some example of people dishonestly quoting the article:
Will that do? They aren't particularly notable but they indicate the kind of stuff you see. None of these quotes is actually untrue: the dishonesty lies in their implying that cooling was either the only prediction, or considered much more likely.
Lets take that second pair of quotes and put them into context. Which is page 582: left column: 2 pix, one of J Murray Mitchell, captioned: "Cooling trend of world climate was documented in the 1960's by J Murray Mitchell... Now, he notes, [CO2] pollution may be contributing to an opposite, or warming, tendency". The second is of Reid Bryson (looking particularly wacky) captioned: "'Human Volcano': Read A Bryson of the University of Wisconsin coined that phrase to describe how an exploding population has flung particulate matter, such as dust from cultivation, into the atmosphere. There it blocks solar rays, and surface temperatures drop. In the complex climate equation, this may be the critical factor, he believes." Right column is text "It is possible we are on the brink of a several-decade-long period of rapid warming...", with a text box in bold: "Were the cooling trend to reverse... the earth could warm relatively rapidly, with potentially catastrophic effect. National Science Foundation, 1975", then "The CO2 level is already up by 10% since 1850; by the year 2000, experts say, it may have risen another 20%, enough to cause a 0.6oC rise in average world temperature.". Then we get a new section, about whether particulates warm or cool. Then we get the quote: "But the sensitivity of climate was pointed up independently by a Soviet and an American scientist, who conclused that a permanent drop of only 1.6 to 2 percent in energy reaching the earth 'would lead to an unstable condition in which continental snow cover would advance to the Equator... [and] the oceans would eventually freeze,' according to a recent U.S. scientific advisory report. [WMC: nb: ellipsis original].
So... its pretty clear from that the they are neither predicting warming nor cooling, and that is what they should have said, given the science of the time.
Before we leave that, lets note that the +20% and +0.6oC by 2000 is about right. And we might also note that the 1.6-2% drop claim is now probably uninteresting, but might still be true.
What's happening to our climate? 576 Cooling in the Northern Hemisphere, thawing in the Antarctic... shifting rain, snow and storm patterns... ice caps, volcanic dust, air pollution, sunspots - the myriad forces that change earth's basic environment are still far from understood. Samuel W. Matthews reviews the weather forecast for tomorrow.
There are various text boxes scattered through the article. Here they are:
p 581: During the last 20 to 30 years, world temperature has fallen, irregularly at first but more sharply over the last decade. U.S. National Science Board, 1974.
p 582: Were the cooling trend to reverse... the earth could warm relatively rapidly, with potentially catastrophic effect. National Science Foundation, 1975.
p 590: The climates of the earth have always been changing, and they will doubtless continue to do so in the future. How large these future chnages will be, and where and how rapidly they will occur, we do not know. National Academy of Sciences, 1975.
p 595: Judging from the record of the past interglacial ages, the present time of high temperatures should be drawing to an end... leading into the next glacial age.... National Science Board, 1972.
p 600; Will we be able to recognize the first phases of a truely significant climatic change when it does occur? NAS, 1975.
p 607: We live in an unusual epoch: today the polar regions have large ice caps, whereas during most of the earth's history the poles have been ice-free. NAS, 1975.
p 610: Man may even be able to change the climate of the earth. This is one of the most important questions of our time. NBS, 1972.
Whew. Is that enough?
I posted a link to this page onto sci.env and received a few comments.
The thread was
Cooling: national geographic, 1976 (googles archive, of course).
The main comment was, the graphs show a LIA. The answer is, they are
artist-drawn and should not be taken too seriously. The last-1000-years
graph is sourced to "air temperatures, eastern Europe". Quite what that
means is unclear. It certainly doesn't mean thermomters
for the 1000 years - the record doesn't go anywhere near that far back.
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I posted a link to this page onto sci.env and received a few comments. The thread was Cooling: national geographic, 1976 (googles archive, of course).
The main comment was, the graphs show a LIA. The answer is, they are artist-drawn and should not be taken too seriously. The last-1000-years graph is sourced to "air temperatures, eastern Europe". Quite what that means is unclear. It certainly doesn't mean thermomters for the 1000 years - the record doesn't go anywhere near that far back.
[Page last modified: 11/11/2004] [ Home] Page proudly created with vi... or vim... or...