[karajorma]

I know, but in general, it's a better term as it covers all the aspects of mankind's influence on the planet. Unless you know that you're only going to be discussing global warming, it's safer to use the catch-all term.

[Alex Heartnet]

My bull **** meter tips into the red at just the mere mention of Fox news let alone being the basis of legitimate discussion. It is a damn shame most of my friends and neighbors take everything they shovel out as truth but that is what I get for living in the south.

This is exactly why one needs to be very picky about exactly WHICH websites to show people.  In this case, I picked poorly - I would of not expected so many people to actually be aware that Fox News is indeed bull ****.    But I don't let that stop me from trying to use such news sources to further my arguments, although I certainly need to take what I see from there with a huge grain of salt.

O RLY.  Given all the dire warnings over the years about massive climate changes that never happened, this is a surprise why?

All of the dire warnings (define "dire") about massive climate changes (define "massive") have stated that said climate changes are a slow process and that we shall feel the effects in the coming 50 or 100 years - it is too early to say that they have not occured - most of them have been made in the past 20 years.

That being said, climate changes are actually occuring. Take a look at Ocean acidification, for example.

Well, it's more of a gut feeling on my part then anything else.  There is just something 'off' about this whole global warming debate that I can't really put into words.
Hard time finding links to back up my claims - it seems like researching this sort of thing would require a major time investment I am not willing to put forth.  But, I found a couple of things.

Here we have a scientist admitting he was being alarmist about climate change.

And, I found this .pdf, which is rather difficult to dismiss as it comes from a US Senator.  Not that I trust our lying politicians either, but this document does make some rather interesting claims that would probably be worth an entire discussion topic in and of itself.

[watsisname]

It is very easy to find people with opinions that go off-scale on either side of the spectrum of global warming / climate change and how severe its effects will be.  This does not mean you should take them as an indicator of the validity of the science involved, nor should it serve as a substitute for actual data.

Perhaps a few questions would help to put your doubts of the topic into words?

-Do you believe that the concentration of greenhouse gases has an effect on the planet's surface temperature?
-Do you believe that the earth has warmed in the last 100 or so years, or is the change fairly insignificant?
-If it has changed, do you think human activities are the primary cause, or is it mostly natural?  Or is it too difficult to tell?


If you want to go over the pdf you linked then that's going to be a very long discussion.  Feel free to pick out what you think is the strongest point it makes and we can discuss it if you like.

[Alex Heartnet]

It is very easy to find people with opinions that go off-scale on either side of the spectrum of global warming / climate change and how severe its effects will be.  This does not mean you should take them as an indicator of the validity of the science involved, nor should it serve as a substitute for actual data.

Perhaps a few questions would help to put your doubts of the topic into words?

-Do you believe that the concentration of greenhouse gases has an effect on the planet's surface temperature?
Yes, but it's really a question of how much of an effect it has.  I don't think it has a significant effect.
-Do you believe that the earth has warmed in the last 100 or so years, or is the change fairly insignificant?
The Earth's climate is constantly changing, yet apparently no scientist has bothered to get historians involved in their climate change research.  Maybe a careful look at medieval literature or something would turn up clues on what the climate was like 500 years ago - historians tend to excel at this type of research, and we DO have written records from back then.
-If it has changed, do you think human activities are the primary cause, or is it mostly natural?  Or is it too difficult to tell?
My belief is that it is mostly natural.  Any manmade global warming is primarily the fault of greedy megacorporations and wasteful big government.  The carbon footprint of the common citizen is quite low indeed compared to larger entities, and manufacturing companies don't really provide many good options for the common citizen that wishes to go green.
This also ties into concerns about personal and economic freedom.  There's a very good reason why people resent having to give up their main means of transportation for the sake of the environment.


If you want to go over the pdf you linked then that's going to be a very long discussion.  Feel free to pick out what you think is the strongest point it makes and we can discuss it if you like.
Oh gosh that is going to involve me actually having to read the 60+ page document and not merely skim over on it.  I'll check back with you on that in a week or so.

[watsisname]

The effects of GHG's on planetary temperature is understood very well.  It's actually rather basic physics.  If not for the Earth's atmosphere, our average surface temperature would be 255 Kelvin.  The atmosphere brings it up to 288.

Doubling the amount of CO2 in the atmosphere (from current levels) results in a roughly 3°C increase in global average temperature.  With error bars, of course.  You can read up on it by searching climate sensitivity and the IPCC has a detailed section about it.

Regarding temperature records, we have do have such records, from multiple proxies, going back hundreds of thousands of years...  The climate of the Medieval period has also been studied extensively.  Not sure why you seem to suggest there may be much discrepancy between that research and what historians would tell you, but uh, if you think there is then by all means look into it.

Some short explanations for how we know that the current global warming is human-caused can be found in the thread on Sub-Polar Methane traps.  I'm also not going to go into the political ramifications of climate change mitigation and what it means for the common-man, maybe others will be interested in discussing that.

Oh gosh that is going to involve me actually having to read the 60+ page document and not merely skim over on it.  I'll check back with you on that in a week or so.

Rightio.  I skimmed through it myself and uh, I don't think it's very credible.  At one portion it claims that fully half of the recent warming was caused by sunspots.  This is quite incorrect -- solar activity plays a very minor role compared to greenhouse gases.  You can see this by comparing data on solar activity to the temperature record, or by comparing the change in radiative forcing of the two.

[Alex Heartnet]

Rightio.  I skimmed through it myself and uh, I don't think it's very credible.  At one portion it claims that fully half of the recent warming was caused by sunspots.  This is quite incorrect -- solar activity plays a very minor role compared to greenhouse gases.  You can see this by comparing data on solar activity to the temperature record, or by comparing the change in radiative forcing of the two.

Well, the thing WAS written by a US Senator.  Did you actually expect the politician who wrote it to tell the truth? 

[watsisname]

No, but in fairness he backs up some of his assertions with links and references, so I don't think it's flat out lying, but perhaps misinformed.

[QuantumDelta]

A lot of people suggest that our climate is controlled by cyclical astronomical events.

Which is quite true. However, we're at a fairly 'average' astronomical period at the moment, and have been more or less, since we left the last ice age.
Ice age triggers and endings have traditionally been during the combination extreme of three cycles, I forget what they all are in honesty, but I do know that we're half way through the most important one (eg; actually average), on the extreme (ice age end) of one of them, and somewhere towards the ice age side of another.

Well, guess what, scientists don't just talk to historians and take in the temperature records (the church of England funnily enough, has kept the most accurate temp record since we had the ability to do so), also taking core samples and tree growth data/etc, this is the warmest it's been in a very long time.
We as a species have never seen it this hot before, not even close.
While it may only be the case of a degree or two, and, on a planetary scale (were it not for things like oceanic acidification), it's not really catastrophic for most life, for us, especially in our current life style, ESPECIALLY if the world aspires to become more like the west in standard of living, it DEEPLY effects our species.

If we can't stop climate change and especially our population growth, even as simple logistics, we will be completely unable to feed people.

[MP-Ryan]

this is the warmest it's been in a very long time.
We as a species have never seen it this hot before, not even close.

Are you completely sure on that? (I'm genuinely asking).  Homo sapiens has been around for 100-130 thousand years.  There've been a couple freeze/thaw cycles, including some large ones, in that period.  I know there are definitely warmer periods in the planet's history than now, and I thought some of them occurred within our species' timeline.  Can you point to the data on this?

If we can't stop climate change and especially our population growth, even as simple logistics, we will be completely unable to feed people.

Welllllllllll... one side effect of increasing global (and ocean) temperatures is better conditions for algal growth, and several species of algae contain the correct nutrient balances to sustain human life.  I agree with you on the logistics, though.

[Flipside]

I've seen a graph showing a correlation between CO2 and Average temperate and show that the CO2 levels are fast approaching their highest for several million years, but I'm not sure I've seen any evidence that the Temperature is at its highest for an equal amount of time, since more things influence temperature than CO2 levels.

I seem to recall that the Permian period was considerably warmer than current days, but that was at a world average, i.e. the Poles were quite heavily forested around that period.

Edit: Permian, not Cretaceous.

[Ghostavo]

http://www.guardian.co.uk/environment/2012/jun/01/north-carolina-sea-level-rises?newsfeed=true

I... wha.... but... uhh?

[watsisname]

It was a bit warmer around 125,000 years ago, at the peak of one of the ~100,000 year temperature cycles.  Today we have pushed CO2 levels well past those of that time, and temperature has yet to respond fully.  When it does it is expected to be higher as well.  image

Going back farther, the temperature was much higher in the early to mid Miocene (~20 million years ago), and the Eocene Optimum roughly 50 million years ago.

I have found fossil palm leaves in northwestern Washington State from the Eocene Optimum; fascinating period in Earth's history.



edit: 

These rates shall only be determined using historical data, and these data shall be limited to the time period following the year 1900. Rates of seas-level rise may be extrapolated linearly ...

...Wow.  They just went full retard.

[Flipside]

To be honest, I've always found the various Mass-Extinctions fascinating, in fact, probably the most scientifically 'boring' one is the end of the Dinosaurs, the others are far more interesting and worrying, since many of them were (a) Terrestrial in origin and (b) Repeatable.

And technically, yes, an Asteroid is repeatable, but the real killer in that Extinction was the breaking of the delicate food chain for animals that had grown dependent on vast quantities of food per day. Carnivores got big, Herbivores got huge, and that was the noose around their own neck.

[QuantumDelta]

Apologies, I honestly forgot about that 'short' cyclical pattern that was observed for that ~400k years.
Although I am fairly sure the first image is the one I have in my head and is the generally accepted standard for the last 450k years, the second image watsisname links has a bit of statistical trickery to it, the sliding scale makes the warming currently observed much less dramatically sharp than it is.

While, again; as I said in my previous post, the earth has been much, much hotter, we, much like the dinosaurs, are already VERY quickly approaching the 'delicate food chain' situation, simply because of our population.
If the climate changes too much in certain areas of the planet, we are pretty boned.

Edit;
I should also mention (again) that those cyclical events were mostly astronomical in origin, we are not currently due for such a heat spike... (again though; we're also not really due an ice age, cuz that was a rumour I saw circulated but never substantiated online (not here?)).

[watsisname]

Although I am fairly sure the first image is the one I have in my head and is the generally accepted standard for the last 450k years, the second image watsisname links has a bit of statistical trickery to it, the sliding scale makes the warming currently observed much less dramatically sharp than it is.

Correct, the current warming trend is very dramatic in terms of rate of change.  The first image shows this pretty well with the CO2 curve (the vertical red spike at the very end), but the second image focuses on what happened on geologic timescales rather than the last 100 or so years.

[Flipside]

With regards to the Ice Age, it was a Media misinterpretation, the statement made was that an Ice Age was due soon from a Geological standpoint, probably within the next 100,000 years. The Media made a big deal of the first half of the sentence and forgot to report the second half

[Alex Heartnet]

With regards to the Ice Age, it was a Media misinterpretation, the statement made was that an Ice Age was due soon from a Geological standpoint, probably within the next 100,000 years. The Media made a big deal of the first half of the sentence and forgot to report the second half

Well, the media seems to be in the habit of trying to scare people.  It's one of the biggest complaints about the big news agencies.

[watsisname]

Stories of imminent doom sell a lot better than stories of gradual doom.

[QuantumDelta]

http://phys.org/news/2012-06-evidence-impending-earth-uncovered.html
Ignore the article title and read on :x