Could it be that Global Warming is a myth?

Question

Last summer was rather more hot and sunny in the UK then usual. Some people attributed this to Global Warming. However surely if Global Warming is caused by excess gases like CO2 creating a "greenhouse effect" this should make no difference to how sunny it is. The sun will shine or not shine no matter what.

Answer 1

Global Warming is generally accepted as a fact. I.E. it is generally accepted that, over the last century, average global temperatures have risen. How much is open to debate, but the usual figure quoted is 0.6°C. So, Global Warming is *not* a myth.

What *is* under a great deal of dispute is what is *causing* this Global Warming. The suggestion that it is being caused by human activity may well be a myth.

The truth is that, as yet, nobody knows for sure. Despite what you may hear from some people, the whole "Global Warming is caused by human activity" theory is *not* a "done deal". There are an awful lot of scientist around who dispute that suggestion. There are some, for example, who say that just about all of the current temperature increases could have been caused by the Sun getting hotter.

You hit on another area that scientists disagree on. Will increasing temperatures cause there to be more or less sunshine? In other words, will increasing temperatures cause more or less cloud cover? There are two conflicting theories...

A) Increasing temperatures will cause more evaporation of water from the sea. This increase in the amount of water vapour in the atmosphere will cause more clouds.

B) Increasing temperatures will warm the air. Warmer air can hold more water without forming clouds. Therefore there will be less cloud cover.

As yet, nobody knows which of the two theories will win out.

Also, there is an awful lot of nonsense spouted on the subject. Several people on this question have mentioned the ozone layer. The truth is that, since CFCs were banned several years ago, the hole in the ozone layer has been disappearing fast and is no longer a problem. Oh, and anyway, the ozone layer has no affect on climate!

MattieP mentions the "accelerated melting of the polar icecaps " - actually 80% of the Antarctic glaciers (that are being monitored; there over 100 thousand of them, so they're not all being watched) are *growing*!

David R said "The CO2 doesn’t affect the sun but it does affect the amount of UV radiation hitting the earth" - Err? No actually, quite the opposite. CO2 affects the amount of radiation from the sun that escapes back out into space, thus trapping it and warming us up. *But*, while this is true, and CO2 levels have risen by about a third in the last century, nobody is sure exactly how much of an affect that is having on the climate. And when you consider that CO2 constitutes less than 1% of greenhouse gas in the atmosphere, you have to wonder whether it can be having that much of an affect, don't you?

In summary, the jury is still very much "out" on the subject of what is causing Global Warming. It is, therefore, far too early to start taking action based on any particular theory. We have to wait until there is a consensus of opinion before we decide what course of action to take. Otherwise we may end up making the problem worse. And no one wants *that*, do they?

Answer 2

Global warming refers to an increase in temperature at the earth's surface. The amount of solar radiation (i.e. the amount of sunshine) is not entirely dictate the temperature.

For instance, on the moon, there is the same amount of solar radiation as there is on the same area of earth. However, the moon has no atmosphere so on the day side it is extremely hot since there is not ozone layer to block rays. On the dark side it is extremely cold because no gases are present to 'trap' the heat.

On Earth, gases like CO2 and water vapour play a significant role in the earth's temperature. Water has a relatively very high heat capacity and will hold vast amounts of heat. CO2 stores heat in other ways. These gases act like a blanket around the earth, keeping it warm.

Global warming is a run away reaction. An increase in water vapour causes the planet to heat up. The extra heat causes more water to evaporate from the oceans to the atmosphere. This increase in water.....so on and so forth.

CO2 in the atmosphere is caused by human activity and volcanic activity.

Global warming is definitely real since the planet IS warming up. However, I am still not convinced it's entirely due to human presence. Once upon a time there was an ice-age. The planet warmed up since then without human interference. A natural phenomenon perhaps. I'm not saying we're not to blame - I'm saying I'm not _yet_ entirely convinced.

Answer 3

It could be a myth. The Earth has always gone through phases. No doubt, though, that we need to start taking care of it - take steps to stop polluting the air and seas, produce less plastic.

But, plastic is a by-product of the oil industry. CO2 is also caused by the burning of fossil fuels, which are predicted to run out in 50 years....so maybe the man-made 'global warming' problem will go away!!!

Answer 4

Global Warming has all the earmarks of a modern myth. There is absolutely no evidence presented to date that is not explainable without GW being true. Dire predictions made based on the more drastic interpretations of GW have not proven accurate. The basic premise cannot be dismissed but it has become the whipping boy of politicos and the agenda-driven.

As a general rule, I don't believe anything that politicians and lobbying groups tell me until I see the facts first.

Answer 5

Global warming itself is not a myth, but there are many myths surrounding it. Like for example that the ice of the polar caps will melt and cuase the sea level to rise. Actually most of the ice of the polar caps is neatly stored at -40°C. Increases of a few °C will not melt it. But what can cause the oceans to rise is warming of the sea water. As you may know metal expands when heated and so does water. Water doesn't expand much (if I remember the numbers correctly it expands by 0,01% per °C), but there are huge quantities of water in the oceans and if we assume that the average depth of the ocean is 4 km, that yields a rise of the water level of 0,4 m per °C of warming.

Where warming strikes hardest is in the areas that are around 0°C in temperature. Like high mountains and the sub polar regions (like Alaska, Canada, Scandinavia and Siberia).

For Americans: 1 m is slightly more than 1 yard, 1 mile = 1,6 km, 0°C is the melting point of ice and 100°C is the boiling point of water (at normal pressure)

Answer 6

The sun always shines
The CO2 doesnt affect the sun but it does affect the amount of UV radiation hitting the earth
I think there may be a case for Global Warming when its warm and sunny in November
What evidence would persuade you?

Answer 7

The sun's strength is obviously affected by what it has to shine through eg the ozone layer. The thicker the layer, the less sun that reaches us and vice versa. There is a lot of evidence for global warming eg the accelerated melting of the polar icecaps

Answer 8

i was under the impression that the holes in the ozone layer allow more UV rays from the sun through, if the UV rays can get through it stands to reason that more heat can get through. With more heat inside the ozone layer surely the clouds would be less prevelant and would dissipate easier - leading to more sunshine.

Just a thought!!

I worked abroad for a number of years in ski resorts and there was a definite difference year to year in the length and starts and finishes of seasons.

Answer 9

Rivig is quite right, we have not caused global warming, but our parents may not have helped, and so we must be care-full not to make things worst for our children, this could last for a hundred or so years, one last thought, in the early 80's we were told we were heading for another ice age, I wonder what happened to that.

Answer 10

Perhaps Global warming is just something that happens to the Earth every now and again. after all it was hot when life on earth began, then we had an ice age, then the earth heats up again.