Cyclist flips Trump the bird as she joins motorcade procession

PRSboy wrote:

Why does it have to be all about temperature overall, or indeed sea levels overall, as about changing temperatures in certain areas destroying habitats, food sources and species?

Reducing whether or not climate change is occuring to simply 'the earth's temperature' is surely to risk missing the detail that matters.

The two together though. If you increase the total energy budget, on average it will get warmer, but it obviously won't get uniformly warmer everywhere, and some places might actually get colder. But more energy in the system means more extreme events and rapid change.

FluffyKittenofTindalos wrote:

Sea level rise is also driven by thermal expansion of the oceans. I believe currently that's the more important factor than land-ice melt.

Currently, it's around 50/50 but thermal expansion will have a greater affect in future, partly due to the increased water mass from the melted ice.

hawkinspeter wrote:

@davel - just because a significantly hotter planet can support life does not mean that I'd like to live there or that it could support human life.

More importantly, we need to look after planet earth as I keep all my stuff there.

There's also the question of the speed at which we transition to that warmer earth. And that there's now rather a lot of investment in infrastructure (too little of it cycle-related) that can't easily be moved.
(Like that XKCD graph - Davel's posted graph is a logarithmic scale, so that speed of transition question isn't clear on it)

The Earth was a lot warmer in past eras, but much of what we currently live on was under water.

FluffyKittenofTindalos wrote:

hawkinspeter wrote:

@davel - just because a significantly hotter planet can support life does not mean that I'd like to live there or that it could support human life.

More importantly, we need to look after planet earth as I keep all my stuff there.

There's also the question of the speed at which we transition to that warmer earth. And that there's now rather a lot of investment in infrastructure (too little of it cycle-related) that can't easily be moved.
(Like that XKCD graph - Davel's posted graph is a logarithmic scale, so that speed of transition question isn't clear on it)

The Earth was a lot warmer in past eras, but much of what we currently live on was under water.

Agree on all points - plus we don't know the effects yet of all the extinctions that we've already seen or are imminent.

hawkinspeter wrote:

@davel - just because a significantly hotter planet can support life does not mean that I'd like to live there or that it could support human life.

More importantly, we need to look after planet earth as I keep all my stuff there.

We are in total agreement there.

I'm just making the point, because it seems that a lot of ideological knee-jerkers still hear this and shout 'denier' like they shout 'Brexiter' or whatever else the Graun is telling them to shout, that it is possible to think that, and still believe that we are living in a particularly favourable, exceptionally stable period. If we're thinking long-term, it's probably wise to plan for another ice age or greater sea rises being round the corner, rather than the 2m/2° changes we're trying to avoid at the moment.

Unfortunately, while we have governments thinking in 5-year terms, and chief execs of oil companies thinking of their pension, and people picking either side on the Internet, I don't think we're going to get that. Either side 'winning' won't do it for me. We still don't know enough about climate change in general.

Edit - 'Grant'? Graun

davel wrote:

hawkinspeter wrote:

@davel - just because a significantly hotter planet can support life does not mean that I'd like to live there or that it could support human life.

More importantly, we need to look after planet earth as I keep all my stuff there.

We are in total agreement there.

I'm just making the point, because it seems that a lot of ideological knee-jerkers still hear this and shout 'denier' like they shout 'Brexiter' or whatever else the Grant is telling them to shout, that it is possible to think that, and still believe that we are living in a particularly favourable, exceptionally stable period. If we're thinking long-term, it's probably wise to plan for another ice age or greater sea rises being round the corner, rather than the 2m/2° changes we're trying to avoid at the moment.

Unfortunately, while we have governments thinking in 5-year terms, and chief execs of oil companies thinking of their pension, and people picking either side on the Internet, I don't think we're going to get that. Either side 'winning' won't do it for me. We still don't know enough about climate change in general.

But most of those large-scale long-term changes are due to mechanisms we understand quite well (e.g. Milankovich cycles). And they tend to operate on scales that are far more long term than even the most far-sighted politician is ever going to prepare for. You might as well suggest we need to start preparing for when the Sun goes nova.
We know enough about 'climate change in general' given the time scales involved.

FluffyKittenofTindalos wrote:

But most of those large-scale long-term changes are due to mechanisms we understand quite well (e.g. Milankovich cycles).

OK - quick Google to confirm he was the orbit bloke...

I thought there was quite a bit of skepticism about the fit of these cycles and there was another school that suggested there was another glacial imminent (apologies if this is way off - been a while since I read anything on this)? Is this all smoothed over now? (hoping for a simplish 'yes' - not expecting you to do my Googling for me)

davel wrote:

Can I avoid being labelled a Denier if I agree that the greenhouse effect is real, and man-made emissions contribute, but also think that 1 the issue is politicised and politicians are extremely likely to fuck up the response (see the EU vehicle emissions tests for laughably ineffective controls on pollution, and global dimming as a potential unintended consequence of 'steaming in') 2 man-made impacts could well be a drop in the ocean compared to what earth is likely to be undergoing naturally?

I'm curious about what the earth may be undergoing naturally. What kind of mechanism are you referring to? (e.g. increased sun output)

hawkinspeter wrote:

davel wrote:

Can I avoid being labelled a Denier if I agree that the greenhouse effect is real, and man-made emissions contribute, but also think that 1 the issue is politicised and politicians are extremely likely to fuck up the response (see the EU vehicle emissions tests for laughably ineffective controls on pollution, and global dimming as a potential unintended consequence of 'steaming in') 2 man-made impacts could well be a drop in the ocean compared to what earth is likely to be undergoing naturally?

I'm curious about what the earth may be undergoing naturally. What kind of mechanism are you referring to? (e.g. increased sun output)

I mean temperature changes and sea-level fluctuations that are completely independent of human tinkering, and are more extreme than the effects of human tinkering.

Eg. if you look at the sea levels for say the past 100 million years, an average from the various models is around 100 metres higher than they are now. And yet, 10,000 years ago, you could have walked to Germany, across Doggerland, past towns that are now 70m under the North Sea.

It's unfortunate (but no coincidence) that we've colonised the planet at the time when sea levels are at pretty much an historic low. We really need to make friends with the Highlanders.

(edited to change 'accident' to 'coincidence' - 'accident' seems to reference design, whereas I was referring to the low sea levels being favourable for human population growth)

davel wrote:

I mean temperature changes and sea-level fluctuations that are completely independent of human tinkering, and are more extreme than the effects of human tinkering.

Eg. if you look at the sea levels for say the past 100 million years, an average from the various models is around 100 metres higher than they are now. And yet, 10,000 years ago, you could have walked to Germany, across Doggerland, past towns that are now 70m under the North Sea.

It's unfortunate (but no coincidence) that we've colonised the planet at the time when sea levels are at pretty much an historic low. We really need to make friends with the Highlanders.

(edited to change 'accident' to 'coincidence' - 'accident' seems to reference design, whereas I was referring to the low sea levels being favourable for human population growth)

Sounds like you're referring to times like the warm minoan period. Although some areas were a lot warmer, other areas were colder and average global temperature was equivalent to mid-20th century temperatures. However, that warming is accounted for by increased solar output, whereas current temperatures don't appear to have any cause other than human-created warming.

So, what mechanism do you think could possibly explain our current global warming?

By the way - check out the latest news on CO2: http://www.bbc.co.uk/news/science-environment-41778089

Here's a handy little pic of average global temperatures (courtesy of https://xkcd.com/1732/):

hawkinspeter wrote:

davel wrote:

I mean temperature changes and sea-level fluctuations that are completely independent of human tinkering, and are more extreme than the effects of human tinkering.

Eg. if you look at the sea levels for say the past 100 million years, an average from the various models is around 100 metres higher than they are now. And yet, 10,000 years ago, you could have walked to Germany, across Doggerland, past towns that are now 70m under the North Sea.

It's unfortunate (but no coincidence) that we've colonised the planet at the time when sea levels are at pretty much an historic low. We really need to make friends with the Highlanders.

(edited to change 'accident' to 'coincidence' - 'accident' seems to reference design, whereas I was referring to the low sea levels being favourable for human population growth)

Sounds like you're referring to times like the warm minoan period. Although some areas were a lot warmer, other areas were colder and average global temperature was equivalent to mid-20th century temperatures. However, that warming is accounted for by increased solar output, whereas current temperatures don't appear to have any cause other than human-created warming.

So, what mechanism do you think could possibly explain our current global warming?

By the way - check out the latest news on CO2: http://www.bbc.co.uk/news/science-environment-41778089

 

Hang on - you're really not going to walk me into the 'bona fide denier' trap. In my original post I said that I accept the greenhouse effect and man's contribution to it. It's undoubtedly having an effect along the lines of our measurements and how far the accurate ones stretch back (50 years?). Should we be doing all we can to tackle that? Absolutely. No axe to grind there.

My point is (and I'm willing to be backed up on this - I haven't 'studied' this and might only be aware of models and studies with an agenda, say the Exxon Sea Level Curve sounds a bit fishy, doesn't it? Maybe I'm a less obvious denier by accident/ignorance) that one of the measurable impacts that we are talking about is along the lines of a prediction of a 2-metre rise in sea level.

During the last ice age, say 20,000 years ago, sea levels were 120m+ lower than they are today.

As I understand it, the sea level models generally suggest that the sea, for most of the earth's hospitable life, has been 100m-200m higher than it is currently. There have been ice ages and thaws that have had perfectly natural causes. I believe there is some debate about whether we're still in an ice age, but my point is that the past 6-8,000 years in particular have been nice and stable, and we have the luxury of worrying about a 2m rise. It hasn't always been like that and it won't be, whether we clamp down on all emissions, or not. Doggerland became Atlantis through zero input from man.

None of this, for me, is saying 'fuck it - just pollute'; the argument has become predictably, depressingly, polarised. We can tackle the impacts of our lifestyles AND understand more about what some of these models might tell us, even if it means that Kevin Costner was right. I'd like to see climate change understood and tackled as 'change in the climate' and not only get funding because of both sides of a row about how much we're fucking up the planet.

davel wrote:

Hang on - you're really not going to walk me into the 'bona fide denier' trap. In my original post I said that I accept the greenhouse effect and man's contribution to it. It's undoubtedly having an effect along the lines of our measurements and how far the accurate ones stretch back (50 years?). Should we be doing all we can to tackle that? Absolutely. No axe to grind there.

My point is (and I'm willing to be backed up on this - I haven't 'studied' this and might only be aware of models and studies with an agenda, say the Exxon Sea Level Curve sounds a bit fishy, doesn't it? Maybe I'm a less obvious denier by accident/ignorance) that one of the measurable impacts that we are talking about is along the lines of a prediction of a 2-metre rise in sea level.

During the last ice age, say 20,000 years ago, sea levels were 120m+ lower than they are today.

As I understand it, the sea level models generally suggest that the sea, for most of the earth's hospitable life, has been 100m-200m higher than it is currently. There have been ice ages and thaws that have had perfectly natural causes. I believe there is some debate about whether we're still in an ice age, but my point is that the past 6-8,000 years in particular have been nice and stable, and we have the luxury of worrying about a 2m rise. It hasn't always been like that and it won't be, whether we clamp down on all emissions, or not. Doggerland became Atlantis through zero input from man.

None of this, for me, is saying 'fuck it - just pollute'; the argument has become predictably, depressingly, polarised. We can tackle the impacts of our lifestyles AND understand more about what some of these models might tell us, even if it means that Kevin Costner was right. I'd like to see climate change understood and tackled as 'change in the climate' and not only get funding because of both sides of a row about how much we're fucking up the planet.

Sea levels have varied a lot over time, but most of the changes have had geological causes. As far as I understand it, the major problem with current sea level rises is that it's due to melting land-based ice. The problem with land-based ice melting is that the albedo of the land reduces (i.e. it reflects less light) which then leads to increased warming.

Here's an informative page from NASA about albedo: https://climate.nasa.gov/resources/education/pbs_modules/lesson2Engage/

You're right in that sea level has been a lot higher, but that's over a geological time scale (millions of years ago) and was before humans existed. Personally, I'd rather not have the sea levels that high again.

Dmurr wrote:

be honest and put forth your platform

sorry, no time for that. Too busy eating white Anglo-Saxon Protestant babies.

ConcordeCX wrote:

Dmurr wrote:

be honest and put forth your platform

sorry, no time for that. Too busy eating white Anglo-Saxon Protestant babies.

woah, don't goad stereotypicaltrollbot0.2 - it was probably coded by a North Korean.