Man Made Global Warming - yet another opinion

economiser

If there is global warming there is virtually nothing we can do about it. Population has trebled since 1940 and will have increased fivefold by 2040. With standards of living rising there will inevitably be shortages of land (goodbye rain forests, pandas etc.), water, fuel etc. The human race is heading like lemmings to disaster.

Never mind. It will probably not happen in the 20 or so years that I have left but I feel for those being born today.

cepheus

The following chart shows the changes in concentrations of CO2 and the Northern Hemisphere temperatures over the past thousand years. If you this doesn't tell you that a) the earth is warming and b) it is almost definitely man made, you need to get your head examined

cepheus

Here is another longer term trend since the last ice age, note the sudden jump after a relatively stable period and inset

cepheus

The Telegraph with the help of imbeciles such as Christopher Booker is dedicated to providing misinformation on issues such as global warming so we don't question the wisdom of greed, waste and consumerism. Like all right wing interests they have little interest in science, society or long term planning for the future, only short term profit for a few.

geordie_joe

cepheus wrote: »

The following chart shows the changes in concentrations of CO2 and the Northern Hemisphere temperatures over the past thousand years. If you this doesn't tell you that a) the earth is warming and b) it is almost definitely man made, you need to get your head examined

Actually, it shows the opposite, if you believe that then you really do need your head examined.

A thousand years ago we didn't know half the world existed, nor were we measuring it temperature. We were not measuring the CO2 either!

The figures in the chart are nothing more than guess work. Not only that, anyone can expand/contract a chart to appear to show anything they like. I once heard of a man who "adjusted" that chart to make it look like a hockey stick!

cepheus

You have no idea what you are talking about, temperature and CO2 are measured by about 7 different means and compared. Statistically this means we know temperatures back around 2000 years reasonably accurately, so if it suddenly rises in the last century you have to be very suspicious of claims of natural explanations etc.

You have been reading to much rubbish from the sceptical press which is designed to mislead. Some of the best scientists in the world (not the bogus nutcases ones dreamt up by the telegraph but properly qualified ones) have examined this, and criticised it in explicit detail before accepting it, that's why we have the IPCC.

Ben84

geordie_joe wrote: »

Actually, it shows the opposite, if you believe that then you really do need your head examined.

A thousand years ago we didn't know half the world existed, nor were we measuring it temperature. We were not measuring the CO2 either!

We might not have been measuring CO2 back then, but we can measure samples from then. Ice cores contain trapped bubbles of gas, samples of the atmosphere when they were formed, and they also having been built from layers of seasonal snow fall have a formation that allows us to count the years back to when they formed. This doesn't just give us the CO2 concentration from the distant past, it's also greatly more accurate than any measurements taken in the past would be as it uses modern techniques and isolated samples.

This is an important part of the known climate record, but the record itself is based on multiple sources and different areas of science. Archaeology is another big contributor. Dating fossils and knowing their aproximate temperature range and environment in which the organisims lived gives a good representation of the climate at that time. We have more methods too, but these are two very different ones that show how we determine the past climate through different sources.

What is so compelling about these sources is how they have independently arrived at the same climate record though seemingly very different methods and reasoning. It's a huge collaborative peice of work that has involved scientists all over the world.

geordie_joe wrote: »

The figures in the chart are nothing more than guess work. Not only that, anyone can expand/contract a chart to appear to show anything they like. I once heard of a man who "adjusted" that chart to make it look like a hockey stick!

The scales on that graph are linear, so it does represent the data as it has been found. I suppose we can debate the data, but the itself graph isn't doing any special effects with it.

geordie_joe

cepheus wrote: »

You have no idea what you are talking about, temperature and CO2 are measured by about 7 different means and compared.

Name six of these means, describe how they are done and show me the result. If you can't do that then you are only repeating a sentence you have heard/read somewhere else.

cepheus wrote: »

Statistically this means we know temperatures back around 2000 years reasonably accurately,

So far you have only said they are accurate, you have presented no proof.

cepheus wrote: »

so if it suddenly rises in the last century you have to be very suspicious of claims of natural explanations etc.

If is a very big word, why didn't you it "it has"?

cepheus wrote: »

You have been reading to much rubbish from the sceptical press which is designed to mislead. .

I don't read the press, of any sort. I may occasionally read an online article if someone posts a link to it. But when I do I don't notice which paper it came from, nor could I tell you which news papers lean which way.

cepheus wrote: »

Some of the best scientists in the world (not the bogus nutcases ones dreamt up by the telegraph but properly qualified ones) have examined this, and criticised it in explicit detail before accepting it, that's why we have the IPCC.

Some, what conclusion did the others come to?

geordie_joe

Ben84 wrote: »

We might not have been measuring CO2 back then, but we can measure samples from then. Ice cores contain trapped bubbles of gas, samples of the atmosphere when they were formed, and they also having been built from layers of seasonal snow fall have a formation that allows us to count the years back to when they formed. This doesn't just give us the CO2 concentration from the distant past, it's also greatly more accurate than any measurements taken in the past would be as it uses modern techniques and isolated samples.

So, what you are saying is we only have samples from those parts of the world that were frozen a thousand years ago and have remained frozen until the present day.

How do you find the average for the planet from such a small section of the earth?

Ben84 wrote: »

This is an important part of the known climate record, but the record itself is based on multiple sources and different areas of science. Archaeology is another big contributor. Dating fossils and knowing their aproximate temperature range and environment in which the organisims lived gives a good representation of the climate at that time. We have more methods too, but these are two very different ones that show how we determine the past climate through different sources.

But the truth is we don't actually know what the temperature ranges were. We can guess that a particular thing must have lived in a temperature between x and y decrees, but we don't actually know. Man can live in the tropic, as can many other things, but those same things have also survived ice ages. So how can that tell us what the temperature was just by looking at what was alive at a certain time?

Ben84 wrote: »

What is so compelling about these sources is how they have independently arrived at the same climate record though seemingly very different methods and reasoning. It's a huge collaborative peice of work that has involved scientists all over the world.

No, what is so compelling is simply the fact that you want to believe it. Just as you accuse me of reading rubbish, I can accuse you of reading rubbish.

cepheus

Name six of these means, describe how they are done and show me the result. If you can't do that then you are only repeating a sentence you have heard/read somewhere else.

Dendrochronology (tree rings), the isotopic composition of snow, corals, and stalactites, records of the time of crop harvests, the treeline in various locations, and historical records. These can compared to the instrumental record during the last few centuries so they can be used as a proxy prior to this period.

There is no major international institution left that supports climate change scepticism. I am not aware of any practising specialist climatologist who is sceptical about climate change. There are some retired types and non specialists scientists who are still sceptical, however, these turn out to be geologists, astronomers, zoologists etc on closer examination. I have worked in the scientific environmental sector and have never met anyone who has taken this seriously for 25 years, that includes the time even prior to most of the evidence being gathered. It's only during the past decade the fossil fuel industry (particularly Exxon) has realised they will have to do something about it, and got their PR crew working with the US Republican party and right wing press to make it appear as if there is an informed debate going on.

I'm tired of going through the same old stuff, and it only falls into the trap of starting a debate which makes it sound respectable, after it has been long dead and buried. Here is the answer to most of the questions.

http://scienceblogs.com/illconsidered/2008/07/how_to_talk_to_a_sceptic.php