Merged Global Warming Discussion II: Heated Conversation

[batvette]

This thread is a continuation of the original Global Warming discussion. That thread may be found here. Thank you.

Replying to this modbox in thread will be off topic  Posted By: Loss Leader

But if average global temperatures rose whilst one particular factor was producing a negative forcing it's safe to conclude that that particular factor was not a contributor to that particular period of warming.

You're completely wrong in claiming that there was a negative forcing from the solar factor. Why are you assuming that when its output was still greater than its average over the previous 400 years?
Wouldn't the sun have had to have LESS output than its 400 year average to be a negative influence? No merely be less hot than its highest peak?

 

[Pixel42]

You're completely wrong in claiming that there was a negative forcing from the solar factor. Why are you assuming that when its output was still greater than its average over the previous 400 years?
Wouldn't the sun have had to have LESS output than its 400 year average to be a negative influence? No merely be less hot than its highest peak?

I was answering your question about the contributions of the various factors over the last 35 years only, during which average global temperatures have risen whilst average solar irradiance has slightly reduced.

http://en.wikipedia.org/wiki/File:Solar-cycle-data.png

 

[batvette]

I was answering your question about the contributions of the various factors over the last 35 years only, during which average global temperatures have risen whilst average solar irradiance has slightly reduced.

http://en.wikipedia.org/wiki/File:Solar-cycle-data.png

If we were only looking at temperature data over the 35 year period that would be a valid observation but we aren't.
Now you're implying it was my question that's caused you to improperly apply data to the discussion.
Let me repeat the point.
Why would you apply the solar influence as a cooling factor in the overall scheme in the latter quarter or so of the 20th century when its output was still higher than the average output over the time the temperature is being observed?
Why look at temperature over 400 or 2000 years then look at solar activity for just 35 then pretend it's meaningful?
The word "equilibrium" is used and the way you apply the solar factor is considering that the equilibrium starts at a point when the sun's output was at a 400 year peak and all should be compared to that in the 35 years since.

 

[Pixel42]

If we were only looking at temperature data over the 35 year period that would be a valid observation but we aren't.

You asked a specific question, I answered it. The exchange is still there for all to read, and is clearly about the possible sources of climate forcings in the last 35 years.

No-one has disputed that solar irradiance has been producing a positive forcing for most of the last 400 years. It cannot, however, account for more than a fraction of the warming that has occurred in the last century or so, as several posters have already explained.

 

[Reality Check]

If we were only looking at temperature data over the 35 year period that would be a valid observation but we aren't.

That is correct, batvette, - we are looking at all of the temperature and TSI data.
The science as explained in Solar activity & climate: is the sun causing global warming? shows that

1. In the last 35 years that output fro the Sun has decreased wile temperatures have increased. Thus the Sun is not responsible for the global temperature increase in the last 35 years.
2. "In the past century, the Sun can explain some of the increase in global temperatures, but a relatively small amount."

Why would you apply the solar influence as a cooling factor in the overall scheme in the latter quarter or so of the 20th century when its output was still higher than the average output over the time the temperature is being observed?

For the simple reason that the Sun's output was lower than the average output over the time the temperature was being observed ! That is what a deceasing trend means.

No one "applied" the solar influence as a cooling factor. The solar influence was measured to have a cooling factor:

• "Foster and Rahmstorf (2011) used multiple linear regression to quantify and remove the effects of the El Niño Southern Oscillation (ENSO) and solar and volcanic activity from the surface and lower troposphere temperature data. They found that since 1979, solar activity has had a very slight cooling effect of between -0.014 and -0.023°C per decade, depending on the data set (Table 1, Figure 3)."
• "Like Foster and Rahmstorf, Lean and Rind (2008) performed a multiple linear regression on the temperature data, and found that while solar activity can account for about 11% of the global warming from 1889 to 2006, it can only account for 1.6% of the warming from 1955 to 2005, and had a slight cooling effect (-0.004°C per decade) from 1979 to 2005."

Why look at temperature over 400 or 2000 years then look at solar activity for just 35 then pretend it's meaningful?

Why do you think that the scientists did something as idiotic as this, batvette?
The scientists looked at the temperature over 400 years and the solar output for 400 years, e.g.

"Total Solar Irradiance from 1713 to 1996 (Wang 2005)"
"Total Solar Irradiance as measured by satellite from 1978 to 2010"
​

The word "equilibrium" is used and the way you apply the solar factor is considering that the equilibrium starts at a point when the sun's output was at a 400 year peak and all should be compared to that in the 35 years since.

What is this "400 year peak", batvette - do you think that the Sun's output was actually at a peak 400 years ago?

That is not what the word "equilibrium" means, batvette:

equilibrium (plural equilibriums or equilibria)

1. The condition of a system in which competing influences are balanced, resulting in no net change. ...
2. (physics) The state of a body at rest or in uniform motion in which the resultant of all forces on it is zero.
3. (chemistry) The state of a reaction in which the rates of the forward and reverse reactions are the same.
4. Mental balance.

 

[DC]

You're completely wrong in claiming that there was a negative forcing from the solar factor. Why are you assuming that when its output was still greater than its average over the previous 400 years?
Wouldn't the sun have had to have LESS output than its 400 year average to be a negative influence? No merely be less hot than its highest peak?

no , not at all. you did not do much reading on the topic, beside some denier Blogs?
get yourself informed on the topic.

when the TSI is sinking, thats a negative forcing no matter how high the TSI was before, when the TSI is rising ist a positive forcing. no matter how high or low the TSI was before.

Solar and climate experts from around the world have looked into this. and ist clear that the late 20th century warming cannot be explained by the sun, actually the only explenation that works is the increased CO2 Levels.

face it. those are the Facts, deal with them.

 

[CapelDodger]

July, and things begin to move in the Arctic Ocean.

http://nsidc.org/data/seaice_index/images/daily_images/N_timeseries.png

http://neven1.typepad.com/blog/2013...the-arctic-goes-pop/comments/page/2/#comments

There's another remarkable animation from A-Team in the Comments at Neven's.

 

[lomiller]

You're completely wrong in claiming that there was a negative forcing from the solar factor. Why are you assuming that when its output was still greater than its average over the previous 400 years?

AGAIN, any forcing more than ~30 years old is already fully built in, the Earth does not continue to warm forever due to a forcing. Even if you don’t understand how it works, the assumption of indefinite warming in response to a positive forcing IS what your faulty assumption is built on.

Wouldn't the sun have had to have LESS output than its 400 year average to be a negative influence? No merely be less hot than its highest peak?

No. The Sun needs to have less output than 30 years ago in order to have a cooling influence. This is because the Earth was already as warm as it was ever going to get from that level of solar output and any decrease can only reduce global temperatures.

 

[bobwtfomg]

New report from the WMO http://library.wmo.int/pmb_ged/wmo_1119_en.pdf

the warmest decade
The period 2001–2010 was the warmest
decade on record since modern
meteorological records began around the
year 1850. The global average temperature
of the air above the Earth’s surface over the
10-year period is estimated to have been
14.47°C ± 0.1°C. This is 0.47°C ± 0.1°C above
the 1961–1990 global average of +14.0°C and
+0.21 ± 0.1°C above the 1991–2000 global
average. It is 0.88°C higher than the average
temperature of the first decade of the 20th
century (1901–1910).
A pronounced increase in the global
temperature occurred over the four decades
1971–2010. The global temperature increased
at an average estimated rate of 0.17°C per
decade during that period, while the trend
over the whole period 1880–2010 was only
0.062°C per decade. Furthermore, the
increase of 0.21°C in the average decadal
temperature from 1991–2000 to 2001–2010
is larger than the increase from 1981–1990
to 1991–2000 (+0.14°C) and larger than for
any other two successive decades since the
beginning of instrumental records.

 

[Abdul Alhazred]

Deserts 'Greening' from Rising Carbon Dioxide

Deserts 'Greening' from Rising Carbon Dioxide: Green Foliage Boosted Across the World's Arid Regions
Science News

So ...

CO₂ is sure enough increasing big time. Really no question about that bit.

We also know there has been no warming since the 1990s.

The world ecosystem is adapting and the outcome is beneficial to humans.

So maybe crisis politics is not only not the answer, but actually harmful to the world if it's successful.

That's aside from arguments about it being ineffective or freedom and prosperity being harmed.

 

[geni]

We also know there has been no warming since the 1990s.

False:

http://www.skepticalscience.com/global-warming-stopped-in-1998.htm

 

[Mikemcc]

Deserts 'Greening' from Rising Carbon Dioxide: Green Foliage Boosted Across the World's Arid Regions
Science News

So ...

CO₂ is sure enough increasing big time. Really no question about that bit.

We also know there has been no warming since the 1990s.

The world ecosystem is adapting and the outcome is beneficial to humans.

So maybe crisis politics is not only not the answer, but actually harmful to the world if it's successful.

That's aside from arguments about it being ineffective or freedom and prosperity being harmed.

Did you read the whole thing?

Probably not.

The readings in the desert were commented on because it's relatively easy to measure the changes. It's almost impossible to measure the changes in other habitats because they are so small.

Yes there is a CO2 fertilisation effect, but it's very small and easily swamped by other factors - lack of water, nutrients, suitable soil types, etc.

ETA: Seconded on wot Geni said. That really is a very tired old meme.

 

[Fudbucker]

Deserts 'Greening' from Rising Carbon Dioxide: Green Foliage Boosted Across the World's Arid Regions
Science News

So ...

CO₂ is sure enough increasing big time. Really no question about that bit.

We also know there has been no warming since the 1990s.

The world ecosystem is adapting and the outcome is beneficial to humans.

So maybe crisis politics is not only not the answer, but actually harmful to the world if it's successful.

That's aside from arguments about it being ineffective or freedom and prosperity being harmed.

Wrong. Warming is occurring in the deep oceans at an unprecedented rate. Water has a high heat capacity, but it's not infinite. When this little atmospheric warming hiatus ends, and heat starts moving back to the atmosphere, it's going to pack a hell of a punch.

 

[crescent]

From the OP:

"On the face of it, elevated CO2 boosting the foliage in dry country is good news and could assist forestry and agriculture in such areas; however there will be secondary effects that are likely to influence water availability, the carbon cycle, fire regimes and biodiversity, for example," Dr Donohue said.

(Bolding added)

Here in the Mojave desert where I live, increases in growth rates lead to small annual plants filling the gaps between the larger perennial plants. These gaps would otherwise have been bare ground (it is a desert, after all). Without the bare ground between the larger plants, wildfire can easily move from one perennial to another. So, we get many more active fire seasons than we had before. This burns off the larger plants, leaving us only with the little annual plants, for a net loss of biomass. In many areas, this overall loss of biomass is quite significant relative to the total present.

In fact, it is quite smoky today, due to some large fires burning over 100 miles west of here.

ETA: We get a loss of biodiversity as well, as the little annual plants are mostly non-native and they perpetuate the fire cycle in a way that does not allow the perennial natives to recover.

 

[OMGturt1es]

Form the article:

"Our work was able to tease-out the CO2 fertilisation effect by using mathematical modelling together with satellite data adjusted to take out the observed effects of other influences such as precipitation, air temperature, the amount of light, and land-use changes."

 

[Tiktaalik]

From the OP:

(Bolding added)

Here in the Mojave desert where I live, increases in growth rates lead to small annual plants filling the gaps between the larger perennial plants. These gaps would otherwise have been bare ground (it is a desert, after all). Without the bare ground between the larger plants, wildfire can easily move from one perennial to another. So, we get many more active fire seasons than we had before. This burns off the larger plants, leaving us only with the little annual plants, for a net loss of biomass. In many areas, this overall loss of biomass is quite significant relative to the total present.

In fact, it is quite smoky today, due to some large fires burning over 100 miles west of here.

ETA: We get a loss of biodiversity as well, as the little annual plants are mostly non-native and they perpetuate the fire cycle in a way that does not allow the perennial natives to recover.

This is exactly what I was going to say. More 'greening' = wildfires in non-fire-adapted environments. Witness: cheat grass.

 

[Abdul Alhazred]

This is the best I can do on short notice, but I won't really get into it before this evening:

http://www.bbc.co.uk/news/science-environment-22567023

in the meantime let me see if I understand the contrary position correctly.

• Climate change is not just happening, it is a crisis.
  
  As it might be terrorism, gun violence, or childhood obesity. And that requires giving more power than ever to the same old corrupt politicians. Or the UN.
  
  Freedom? Prosperity? Constitution?
  
  Oh please. It's a crisis.

 

[MikeG]

This is the best I can do on short notice, but I won't really get into it before this evening:

http://www.bbc.co.uk/news/science-environment-22567023

I'm not convinced you actually read the stuff you link to. In that BBC article, these are the first few lines:

Scientists say the recent downturn in the rate of global warming will lead to lower temperature rises in the short-term............But long-term, the expected temperature rises will not alter significantly

A short-term slow down in the rate of rise. That isn't a reversal of the trend...simply a slowing down of the rate of rise, completely undermining your silly claim that there has been no warming since the 90's..

Mike

 

[crescent]

The OP is linked to a Question and Answer section:

Q: Will this new information change the climate debate?

A: No, these results should not change the climate change debate. They do, however, provide a little more understanding on which to base the debate.
Whilst it may seem that an increase in the uptake of carbon by vegetation would serve to offset the rise in atmospheric CO2 levels, the amounts in question are too small to make a significant difference to the overall global picture.

Q: So does this mean climate change is good for the planet?

A: This does not mean that climate change is good for the planet. Whilst CO2-induced increases in cover across many of the world's deserts and semi-deserts will most likely have some beneficial effects, there will also be associated changes that are seen to be detrimental, like possible decreases in surface water availability or the encroachment of woody vegetation into native pastures.

.... in the meantime let me see if I understand the contrary position correctly.

• Climate change is not just happening, it is a crisis.
  
  As it might be terrorism, gun violence, or childhood obesity. And that requires giving more power than ever to the same old corrupt politicians. Or the UN.
  
  Freedom. Prosperity? Constitution?
  
  Oh please. It's a crisis.

I would settle for admitting that human caused climate change is happening. You don't like it, I don't like it, but what we like or don't like does not matter. It is happening anyway. The truth is sometimes, you know, inconvenient.

ETA: To keep this on track as somewhat separate from the general topic of climate change - the "Greening" effect is very limited and has only been documented in Australia. Not all plants might benefit from it, much the way some plants can take advantage of excess soil nitrogen compared to other plants. Unfortunately, the plants that like the nitrogen are the same plants that promote frequent wildfire. This means that in many deserts, more rapid plant growth leads to more fires, and less fixed carbon, less biomass, not more. You drew the wrong results from your two links, they do not actually draw the conclusions that you inferred from them.

 

[rwguinn]

Back when I lived in Roswell, NM, we noticed the greening up of the deserts. Usually after a good rain (Rare, but they do happen)
I defined the color as "Grimly-determined green".
It doesn't last long...