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It's difficult to know which comments are genuine and which are sarcastic.

Examples of long term recession of glaciers:

https://en.wikipedia.org/wiki/Northern_Ice_Field_%28Mount_Kilimanjaro%29

https://en.wikipedia.org/wiki/Puncak_Jaya#Glaciers

https://en.wikipedia.org/wiki/Pine_Island_Glacier

Examples of expanding deserts:

https://en.wikipedia.org/wiki/Gobi_Desert#Desertification

https://en.wikipedia.org/wiki/Aral_Sea

 

Regards the discussion of energy use. Hydrocarbons are unlikely to run out, but are very likely to become increasingly difficult to find and extract in the future. Eventually nuclear reactors, tidal energy, solar energy and so forth will have to replace much of the energy mix. Solar energy is already cheaper than coal in low latitude countries, for example.

Large savings in energy use can be made too, which would help relieve the problem; most people's carbon footprints can realistically be cut by a factor of two already. This will likely become a necessity in the future.

 

@WileyWarWeasel claims that the UK's energy mix is <1% renewable. The UK became >10% renewable energy in 2012: https://www.gov.uk/government/statistics/renewable-sources-of-energy-chapter-6-digest-of-united-kingdom-energy-statistics-dukes

Hydroelectric energy makes up 2% of the UK's energy mix, itself double what Wiley claimed the entire UK energy renewable energy mix constituted.

The UK renewable fraction recently exceeded 25% for the first time.

Hence I would interpret Wiley's comments with a pinch of salt; he has clearly not taken the liberty to verify his comments before posting them.

 

 

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1 hour ago, Saxon said:

 

@WileyWarWeasel claims that the UK's energy mix is <1% renewable. The UK became >10% renewable energy in 2012: https://www.gov.uk/government/statistics/renewable-sources-of-energy-chapter-6-digest-of-united-kingdom-energy-statistics-dukes

Hydroelectric energy makes up 2% of the UK's energy mix, itself double what Wiley claimed the entire UK energy renewable energy mix constituted.

The UK renewable fraction recently exceeded 25% for the first time.

Hence I would interpret Wiley's comments with a pinch of salt; he has clearly not taken the liberty to verify his comments before posting them.

The devil is in the details: the quote that I mentioned was referring to the overall energy used by UK, not just energy used for electricity.

After looking into it a bit further though I'll admit that the figure quoted in the article and the figure I've found are a tiny bit different.

 

According to table 1.02 for 2013, electricity (derived from various sources including renewable) used was the equivalent of 19.7 Mtoe out of the total of 207.0 Mtoe. The percentage of the total is approximately 9.5%.

https://www.gov.uk/government/uploads/system/uploads/attachment_data/file/449103/1._overall_tables.xlsx

 

According to page 5 of the renewable sheet, 14.8% of electricity was derived from renewable resources.

https://www.gov.uk/government/uploads/system/uploads/attachment_data/file/450298/DUKES_2015_Chapter_6.pdf

 

~9.5% * 14.8% = 1.4% of overall energy used in the UK in 2013 was from renewable sources. I'm not sure where exactly the article got its figures for the overall energy from but it's less than 1 percentage point different from what they were claiming. Hope that clears things up :)

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36 minutes ago, WileyWarWeasel said:

The devil is in the details: the quote that I mentioned was referring to the overall energy used by UK, not just energy used for electricity.

After looking into it a bit further though I'll admit that the figure quoted in the article and the figure I've found are a tiny bit different.

 

According to table 1.02 for 2013, electricity (derived from various sources including renewable) used was the equivalent of 19.7 Mtoe out of the total of 207.0 Mtoe. The percentage of the total is approximately 9.5%.

https://www.gov.uk/government/uploads/system/uploads/attachment_data/file/449103/1._overall_tables.xlsx

 

According to page 5 of the renewable sheet, 14.8% of electricity was derived from renewable resources.

https://www.gov.uk/government/uploads/system/uploads/attachment_data/file/450298/DUKES_2015_Chapter_6.pdf

 

~9.5% * 14.8% = 1.4% of overall energy used in the UK in 2013 was from renewable sources. I'm not sure where exactly the article got its figures for the overall energy from but it's less than 1 percentage point different from what they were claiming. Hope that clears things up :)

Your maths assumes that no fraction of non-electrical energy is derived from renewable resources; is that true?

 

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7 minutes ago, Saxon said:

Your maths assumes that no fraction of non-electrical energy is derived from renewable resources; is that true?

 

Pretty much (barring one flimsy exception if you really want to stretch it since I know you'll want to mention it); if you look at table 1.02 in the previous post the fuels are solid fuel, petroleum, gas, "bioenergy and waste" (single category) and electricity.

 

The first three are not being naturally renewed anywhere near as quickly as they're being consumed so we don't count them. The last one from what I can tell is mostly combined waste from the economy and bio fuels. Too bad that crops are grown using various machines (tractors, etc) powered by fossil fuels and waste is a byproduct of our system, not a "naturally renewed" energy source like solar. The two combined are not extracted from the surrounding natural environment (they are produced by the economy) in the same way that "renewable" sources such as solar, wind and tidal energy are.

In my opinion "bio-energy and waste" should not be counted as renewable due to the above but if you want to count them anyway then for 2013 bio & waste was 9.4Mtoe out of 207 Mtoe = 4.5%. Whoopee.

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17 minutes ago, Cingal said:

So... Like...

 

Hypothetically, if Africa was suddenly to just... Not have people in it any more...

 

How would global warming be looking?

Still horrendous. China, India, Russia, and the US are the big four when it comes to ascertaining which countries are the largest contributors to global warming.

 

 

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11 minutes ago, Sir Gibby said:

I don't know if it's complete horseshit or not, but wasn't it predicted that there'd be some sort of "mini ice age" around 2030?

I haven't heard of that before?

I'm guessing you've heard something about sunspot cycles. Periods of unusual warmth or cold in the last millennium happened to occur alongside changes in sunspot frequency. The little ice age, which was unusually cold, occurred at the same time when there were relatively few sunspots (A time known as the 'Maunder minimum') and the sun was hence dimmer. 

This has lead some scientists to suggest that changes in solar output, due to variations in sunspot count, can cause changes in the climate. There has been a long term decrease in sunspot count over the last half century, but on a much smaller scale than the Maunder minimum; rather like a 'mini Maunder minimum'.

Scientists aren't sure whether sunspot changes really were the cause of the little ice age, because the total solar luminosity only changes by ~0.1% due to these changes. (although Ultraviolet radiation changes by a factor of 10 more)

This 0.1% radiation change is much much smaller than the change we've already generated by increasing the greenhouse effect.

Climatologists are not certain why the earth might response so sensitively to changes in the sunspot cycle, so I don't think anybody would be able to forecast another little ice age with any confidence.

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On 5/7/2016 at 3:21 PM, I Did It For The Cat Girls said:

Still horrendous. China, India, Russia, and the US are the big four when it comes to ascertaining which countries are the largest contributors to global warming.

So, nuke China, India, and Russia. Works for me.

On 5/7/2016 at 3:50 PM, Saxon said:

I'm guessing you've heard something about sunspot cycles. Periods of unusual warmth or cold in the last millennium happened to occur alongside changes in sunspot frequency. The little ice age, which was unusually cold, occurred at the same time when there were relatively few sunspots (A time known as the 'Maunder minimum') and the sun was hence dimmer. 

Wouldn't the sun be dimmer if there were a lot of sunspots? I heard from someone that we're in a period of low sunspots right now. And it cycles every 11 years.

 

I'm surprised we don't have any people here (except for the bear on the other page) that are denying man made climate change. Even the more conservative people here believe in it.

It seems like in order to be a card carrying member of mainstream GOP or Tea Party style conservatism, or even many libertarians, you have to automatically believe climate change is a hoax. Not just healthy scientific doubt or skepticism, because good science should always be trying to check itself. But flat out "this doesn't exist, this never existed, this will never exist, anyone who says otherwise is crazy." Must hurt being that stupid, I guess.

I would say it's a combination of the religious right locking itself so closely with the GOP and business right to combat communism during the cold war, the hippy sexual revolution, and row vs wade. The religious people couldn't imagine that Man could change GOD's creation so much as to pose a danger to humanity. And the energy sector, fearing heavy regulation by environmental nuts, went into denial mode rather than just showing how regulation could raise energy prices. Eventually, it became dogma and orthodox to believe it's all fake.

And it's interesting to see what kind of excuses I see to explain why man made climate change actually exists. The most common one is that climate change was created to destroy capitalism and create the big government communist world liberals desire. Not only is that tin-foil hat conspiracy lunacy, it doesn't really survive occam's razor. Is it really possible that the EPA has a world wide conspiracy, and that every single climate scientist on the planet is in on this massive conspiracy? Seems a bit far fetched.

 

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6 hours ago, Crazy Lee said:

So, nuke China, India, and Russia. Works for me.

Wouldn't the sun be dimmer if there were a lot of sunspots? I heard from someone that we're in a period of low sunspots right now. And it cycles every 11 years.

 

I'm surprised we don't have any people here (except for the bear on the other page) that are denying man made climate change. Even the more conservative people here believe in it.

It seems like in order to be a card carrying member of mainstream GOP or Tea Party style conservatism, or even many libertarians, you have to automatically believe climate change is a hoax. Not just healthy scientific doubt or skepticism, because good science should always be trying to check itself. But flat out "this doesn't exist, this never existed, this will never exist, anyone who says otherwise is crazy." Must hurt being that stupid, I guess.

I would say it's a combination of the religious right locking itself so closely with the GOP and business right to combat communism during the cold war, the hippy sexual revolution, and row vs wade. The religious people couldn't imagine that Man could change GOD's creation so much as to pose a danger to humanity. And the energy sector, fearing heavy regulation by environmental nuts, went into denial mode rather than just showing how regulation could raise energy prices. Eventually, it became dogma and orthodox to believe it's all fake.

And it's interesting to see what kind of excuses I see to explain why man made climate change actually exists. The most common one is that climate change was created to destroy capitalism and create the big government communist world liberals desire. Not only is that tin-foil hat conspiracy lunacy, it doesn't really survive occam's razor. Is it really possible that the EPA has a world wide conspiracy, and that every single climate scientist on the planet is in on this massive conspiracy? Seems a bit far fetched.

 

The sun is brighter when there are more sunspots because the penumbral regions of the spots emit a huge amount of radiation.

The sun spot cycle has an 11 year periodicity, as well as long term trends on multi-decadal and centennial timescales.

On the discussion of religion, it was only relatively (~1796) that scientists such as George Cuvier realised that fossils demonstrated many species had become extinct in the past and that human actions could force extant animals to go extinct too. For a long time people had believed that god would intervene if a species wasn't doing very well and many people thought that fossil species were still alive somewhere. In fact, explorers of the American great west were told by the administration to 'keep an eye out for mammoths'.

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On Saturday, May 07, 2016 at 3:26 PM, Sir Gibby said:

I don't know if it's complete horseshit or not, but wasn't it predicted that there'd be some sort of "mini ice age" around 2030?

There is a chance if global warming continues that parts of the north and south will freeze over due to high temperatures in the poles eliminating the deep ocean currents and stopping a large majority of warm water flow from the equator up the coasts. There was evidence that a long while back this was the cause of one of the main extinctions after the deep ocean currents slowed and killed off a large number of phytoplankton, which give us most of our airborne oxygen, effectively wiping out a large number of the terrestrial animals

 

(Sort of related article for proof or whatever http://www.nap.edu/read/4762/chapter/7)

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36 minutes ago, Astus said:

There is a chance if global warming continues that parts of the north and south will freeze over due to high temperatures in the poles eliminating the deep ocean currents and stopping a large majority of warm water flow from the equator up the coasts. There was evidence that a long while back this was the cause of one of the main extinctions after the deep ocean currents slowed and killed off a large number of phytoplankton, which give us most of our airborne oxygen, effectively wiping out a large number of the terrestrial animals

 

(Sort of related article for proof or whatever http://www.nap.edu/read/4762/chapter/7)

I think you have confused the bi-modal behaviour of the 'meridional overturning circulation' with ocean anoxic events.

The meridional overturning circulation is an ocean conveyor belt, driven by mechanical wind stresses in the southern ocean and the sinking of cold dense salty water in the far north Atlantic ocean. It results in a net northward heat transport in the Atlantic, which is part of the reason that western Europe is unusually warm for its high latitude.

Ice melt can weaken the meridional overturning circulation, or turn the northward heat transport off, by making the North Atlantic less saline and hence preventing the water there from sinking to create a closed circulation.

This is one explanation for the '8.2kya' event, which happened 8.2thousand years ago. The temperature proxy record shows that the North Atlantic became unusually cold, and this event was coeval with the collapse of an ice damn in North America, which added lots of fresh water to the North Atlantic, hence reducing its efficacy as a heat transporter:

http://www.climate.unibe.ch/~born/share/papers/8k/kleiven_kissel08.sci.pdf

 

The meriodinal overturning circulation may weaken if much of the greenland and west antarctic ice sheets melt, but it is unlikely that the afflicted regions will become colder; they simply won't experience as much warming as the rest of the world: http://storm.colorado.edu/~whan/webpage/Publications/Huetal_dsr2011.pdf

 

The Paper you quoted, about the Palaeocene extinction of deep water forams and ostracods due to rapid warming of deep waters, is set about 60 million years ago, when the world had no ice caps at all. It furthermore doesn't propose what you describe. It claims that planktic organisms, including phytoplankton, were unaffected by the Palaeocene-Eocene Thermal Maximum. The paper proposes that warming of the surface oceans in the PETM caused the regions where deep water masses form to become warm too, hence the deep oceans became disproportionately warmer. Warm water holds less oxygen, hence deep areas of the abyssal ocean became anoxic, and this caused some of the creatures that lived there to die. Rather than 'decimating terrestrial animals', the PETM happens to coincide with the evolution of the earliest primates, likely because the humid paratropical conditions of the thermal-maximum suited arboreal animals very well.

 

I hope I've clarified things.

If you want to read more about the PETM: https://en.wikipedia.org/wiki/Paleocene%E2%80%93Eocene_Thermal_Maximum#Evidence_for_carbon_addition

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Earth history has about a million chapters and the processes which determine climate and geological history are very complicated, so I hope none of you feel like I'm being a contrarian when I swoop in and disagree.

I also realise that failing to use plain english can reduce clarity ( I'm pretty sure that my use of the word 'penumbral*' will have lost some people) and that many of the papers being quoted are essentially un-readable if you are not versed in the literature already, so please point it out if my language isn't clear enough.

 

*It just means the outer-edge surrounding a sunspot. The sunspot is dark, but the outer-edge is extremely bright.

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2 hours ago, Saxon said:

I think you have confused the bi-modal behaviour of the 'meridional overturning circulation' with ocean anoxic events.

The meridional overturning circulation is an ocean conveyor belt, driven by mechanical wind stresses in the southern ocean and the sinking of cold dense salty water in the far north Atlantic ocean. It results in a net northward heat transport in the Atlantic, which is part of the reason that western Europe is unusually warm for its high latitude.

Ice melt can weaken the meridional overturning circulation, or turn the northward heat transport off, by making the North Atlantic less saline and hence preventing the water there from sinking to create a closed circulation.

This is one explanation for the '8.2kya' event, which happened 8.2thousand years ago. The temperature proxy record shows that the North Atlantic became unusually cold, and this event was coeval with the collapse of an ice damn in North America, which added lots of fresh water to the North Atlantic, hence reducing its efficacy as a heat transporter:

http://www.climate.unibe.ch/~born/share/papers/8k/kleiven_kissel08.sci.pdf

 

The meriodinal overturning circulation may weaken if much of the greenland and west antarctic ice sheets melt, but it is unlikely that the afflicted regions will become colder; they simply won't experience as much warming as the rest of the world: http://storm.colorado.edu/~whan/webpage/Publications/Huetal_dsr2011.pdf

 

The Paper you quoted, about the Palaeocene extinction of deep water forams and ostracods due to rapid warming of deep waters, is set about 60 million years ago, when the world had no ice caps at all. It furthermore doesn't propose what you describe. It claims that planktic organisms, including phytoplankton, were unaffected by the Palaeocene-Eocene Thermal Maximum. The paper proposes that warming of the surface oceans in the PETM caused the regions where deep water masses form to become warm too, hence the deep oceans became disproportionately warmer. Warm water holds less oxygen, hence deep areas of the abyssal ocean became anoxic, and this caused some of the creatures that lived there to die. Rather than 'decimating terrestrial animals', the PETM happens to coincide with the evolution of the earliest primates, likely because the humid paratropical conditions of the thermal-maximum suited arboreal animals very well.

 

I hope I've clarified things.

If you want to read more about the PETM: https://en.wikipedia.org/wiki/Paleocene%E2%80%93Eocene_Thermal_Maximum#Evidence_for_carbon_addition

You pretty much wrote exactly what i was too impatient to try to explain in the right terms, and correct terminology... so yeah that is right and what I was hoping to go for with the argument that warming temperatures can cause stuff. 

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56 minutes ago, Astus said:

You pretty much wrote exactly what i was too impatient to try to explain in the right terms, and correct terminology... so yeah that is right and what I was hoping to go for with the argument that warming temperatures can cause stuff. 

I reached very different conclusions, so I'm not sure this was what you were trying to say?

 

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26 minutes ago, Saxon said:

I reached very different conclusions, so I'm not sure this was what you were trying to say?

 

Welcome to my finals week... where my brain is so fired I say jumbled bits of information, lol

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