Global warming discussion IV

[Jules Galen]

The Paris Climate Agreement Is Now Official

The historic deal to address climate change will enter into force in 30 days.


73 countries (57% of global emissions) already ratified it.

No. It won't.

Really...Climate Change is just to keep the little people occupied, while the people who run this planet don't care.

So...nothing gets done.

Deal.

 

[Red Baron Farms]

Climate Change is just to keep the little people occupied.

Climate change has no purpose. It is physics. Don't confuse climate change with mitigation proposals. People are working on mitigation, the science showing climate change is both real and caused by humans is already evidenced beyond reasonable doubt.

However, even if what you claim regarding mitigation were true, and it is some ruse to keep little people occupied, a statement like that is pure sloganeering and deserves to be in the conspiracy theory forum, not the science forum. There you can mentally masturbate about wackjob ideas with no evidence beyond your own imaginations all you want. Here we require evidence.

 

[Locknar]

Before it starts down the road of doom....please stay on topic. Discussion re keeping people occupied belongs elsewhere - NOT here.

Posted By: Locknar

 

[Trakar]

New climate sensitivity assessments

Just in time for the deregulation of the fossil fuel industries!

"Nonlinear climate sensitivity and its implications for future greenhouse warming"

(full paper available at)
http://advances.sciencemag.org/content/2/11/e1501923.full

Abstract
Global mean surface temperatures are rising in response to anthropogenic greenhouse gas emissions. The magnitude of this warming at equilibrium for a given radiative forcing—referred to as specific equilibrium climate sensitivity (S)—is still subject to uncertainties. We estimate global mean temperature variations and S using a 784,000-year-long field reconstruction of sea surface temperatures and a transient paleoclimate model simulation. Our results reveal that S is strongly dependent on the climate background state, with significantly larger values attained during warm phases. Using the Representative Concentration Pathway 8.5 for future greenhouse radiative forcing, we find that the range of paleo-based estimates of Earth’s future warming by 2100 CE overlaps with the upper range of climate simulations conducted as part of the Coupled Model Intercomparison Project Phase 5 (CMIP5). Furthermore, we find that within the 21st century, global mean temperatures will very likely exceed maximum levels reconstructed for the last 784,000 years. On the basis of temperature data from eight glacial cycles, our results provide an independent validation of the magnitude of current CMIP5 warming projections.

They are talking about a SAT increase of between 4.78C to 7.36C by 2100,
which is very similar to the higher end calculations of Archer and Hansen.

 

[macdoc]

Beat me to it...not good for human situation.

 

[Puppycow]

Here is something a little more optimistic.

Carbon-hungry plants impede growth rate of atmospheric CO2 (Phys.org)

New findings suggest the rate at which CO2 is accumulating in the atmosphere has plateaued in recent years because Earth's vegetation is grabbing more carbon from the air than in previous decades.

That's the conclusion of a new multi-institutional study led by a scientist from the Department of Energy's Lawrence Berkeley National Laboratory (Berkeley Lab). It's based on extensive ground and atmospheric observations of CO2, satellite measurements of vegetation, and computer modeling. The research is published online Nov. 8 in the journal Nature Communications.

To be clear, human activity continues to emit increasing amounts of carbon, and the atmospheric concentration of CO2, now at 400 parts per million (ppm), continues to rise. But the scientists found that between 2002 and 2014, the rate at which CO2 increased in the atmosphere held steady at about 1.9 ppm/year. In addition, the proportion of the CO2 emitted annually by human activity that remains in the atmosphere declined by about 20 percent. This slowdown can't keep pace with emissions, so the overall amount of human-caused CO2 in the atmosphere increased, just not as quickly. And for that, new research suggests, we can thank plants.

"This highlights the need to identify and protect ecosystems where the carbon sink is growing rapidly," says Trevor Keenan, a research scientist in Berkeley Lab's Climate & Ecosystem Sciences Division and the corresponding author of the paper.

The scientists attribute the stalled CO2 growth rate to an uptick in land-based photosynthetic activity, fueled by rising CO2 levels from fossil fuel emissions. It's a snowball effect: as CO2 levels rise in the atmosphere, photosynthetic activity flourishes and plants take in more carbon, sparking more plant growth, more photosynthesis, and more carbon uptake.

They also identified another player. Plant respiration, a process in which plants use oxygen and produce CO2, did not increase as quickly as photosynthesis in recent years. This is because plant respiration is sensitive to temperature, and it was affected by the recent slowdown in global warming that was observed most significantly over vegetated land. So, between 2002 and 2014, plants took in more CO2 through photosynthesis, but did not "exhale" more CO2 into the atmosphere through respiration.

"These changes decreased the amount of anthropogenic CO2 that stays in the atmosphere, and thus slowed the accumulation of atmospheric CO2," says Keenan.

So that's good. Doesn't totally mean we are free and clear of course, but maybe does mean that there is a natural feedback mechanism that works counter to the forcing, and maybe, just maybe we can get away with smaller reductions in CO2 emissions? And it comes from what looks like a credible source too: "multi-institutional study led by a scientist from the Department of Energy's Lawrence Berkeley National Laboratory".

Here's another article:
For 12 years, plants bought us extra time on climate change (The Verge)

We already knew that oceans and land plants remove about 45 percent of the CO2 emitted by human activities each year. And the amount of CO2 that’s removed has more than doubled in the past 50 years. With plants, which need carbon dioxide to grow, that’s because CO2 increases photosynthesis. So more CO2 in the atmosphere means plants also absorb more CO2. But that doesn’t mean we’re fine pumping the greenhouse gas into the air.

In fact, more CO2 means warmer temperatures, and warmer temperatures cause ecosystems — plants, trees, and even bacteria in soil — to release more CO2 back into atmosphere. So it’s a give and take.

But the study authors realized something they didn’t expect: between 2002 and 2014, the CO2 concentration in the atmosphere wasn’t going up even though people were emitting increasing amounts of carbon dioxide. After analyzing climate measurements and simulations, they figured out that the “give and take” process had been altered.

While the buildup of CO2 in the atmosphere caused plants to absorb increasing amounts of CO2, something else happened that allowed the plants to keep storing this carbon dioxide. From 2002 to 2014, temperatures over global land were increasing but not as dramatically as in the decades before. So the slowdown in warming rates allowed the plants to absorb more carbon dioxide than they released — effectively slowing down the buildup of CO2 in the atmosphere.

Now to be sure, we are still pumping it out faster than the plants can absorb it, and the last two years were the hottest on record. And I don't know that we can assume that plants will continue to take up more and more CO2 but I don't know that that's been ruled out either. But it seems to run counter to the narrative that deforestation was going to "burn the candle at both ends" so to speak. That is, that even as we were pumping out more CO2, because we were also chopping down the rainforests at the same time the plants wouldn't be able to absorb as much CO2. In fact, plants according to this study absorb twice as much as they did 50 years ago.

 

[lomiller]

Here is something a little more optimistic.

Carbon-hungry plants impede growth rate of atmospheric CO2 (Phys.org)

Tamino disputes these findings. When he replicates their work he gets a trend discontinuity. He also notes that the confidence intervals completely overlap.
https://tamino.wordpress.com/2016/11/11/another-pause-claim/

I know the simple comparison of confidence intervals can be misleading, but it actually increases the chance of a false conclusion of trend change, so genuine evidence for a trend change in CO2 growth rate is simply not there. The same conclusion follows from doing it right — by fitting a trend-change model without jump discontinuity, and by fitting a trend-change model with jump discontinuity (and using the Chow test).

 

[Trakar]

Tamino disputes these findings. When he replicates their work he gets a trend discontinuity. He also notes that the confidence intervals completely overlap.
https://tamino.wordpress.com/2016/11/11/another-pause-claim/

While it would be silly to suggest that the combination of warming (particularly in the higher latitudes), and increased CO2 would not lead to increased plant growth, There is, however, no indication of either a significant easing of the problems associated with AGW, much less any real benefits from this study.

The short-term benefactors are weeds and the insects that feed upon them during much longer growing seasons than such latitudes normally allow for.
We are still increasing the amount of CO2 in our atmosphere by ~1.9 ppm/year and that rate is still increasing, just a little slower than it was increasing a decade ago. Once our new administration unfetters the US fossil fuel industry of regulation we will more than correct for acceleration that was slowed more by a poor economy than by the growth of weeds. A lot more methane released upon decomposition.

BAU must be obeyed!

BTW full paper link: http://www.nature.com/articles/ncomms13428#f3

 

[lomiller]

While it would be silly to suggest that the combination of warming (particularly in the higher latitudes), and increased CO2 would not lead to increased plant growth, There is, however, no indication of either a significant easing of the problems associated with AGW, much less any real benefits from this study.

The short-term benefactors are weeds and the insects that feed upon them during much longer growing seasons than such latitudes normally allow for.
We are still increasing the amount of CO2 in our atmosphere by ~1.9 ppm/year and that rate is still increasing, just a little slower than it was increasing a decade ago. Once our new administration unfetters the US fossil fuel industry of regulation we will more than correct for acceleration that was slowed more by a poor economy than by the growth of weeds. A lot more methane released upon decomposition.

BAU must be obeyed!

BTW full paper link: http://www.nature.com/articles/ncomms13428#f3

That’s not really the point of disagreement nor quite what the paper is arguing. For the airborne faction to even remain constant the rate at which the various carbon sinks absorb CO2 has to increase. What the paper is arguing is that the acceleration in the increase of atmospheric CO2 concentrations has stopped or slowed (the rate at which plants etc absorb CO2 hasn’t just grown but that growth has accelerated) and the airborn faction is decreasing.
Tamino applies the same method to the same dataset and time period but gets a differ result than what’s reported in the paper.

Obviously a blog post is not the final word but I’d take this paper with a bigger grain of salt than normal until we have follow-ups.

 

[CapelDodger]

That is, that even as we were pumping out more CO2, because we were also chopping down the rainforests at the same time the plants wouldn't be able to absorb as much CO2. In fact, plants according to this study absorb twice as much as they did 50 years ago.

The extra is in the melting north and boreal forests, not in rain forests.

 

[aleCcowaN]

Particularly with respect to the fatally flawed Paris Climate Agreement, don't you find the phrase "enter into force" at the least somewhat ironic?

... the force of shame?

 

[aleCcowaN]

...Climate Change is just to keep the little people occupied...

...so, you wouldn't have time to know it for sure...

 

[Trakar]

... the force of shame?

LOL,...if only shame didn't require one to acknowledge culpability first!

 

[Trakar]

That’s not really the point of disagreement nor quite what the paper is arguing. For the airborne faction to even remain constant the rate at which the various carbon sinks absorb CO2 has to increase. What the paper is arguing is that the acceleration in the increase of atmospheric CO2 concentrations has stopped or slowed (the rate at which plants etc absorb CO2 hasn’t just grown but that growth has accelerated) and the airborn faction is decreasing.
Tamino applies the same method to the same dataset and time period but gets a differ result than what’s reported in the paper.

[qimg]http://www.nature.com/article-assets/npg/ncomms/2016/161108/ncomms13428/images/w926/ncomms13428-f1.jpg[/qimg]

[qimg]https://tamino.files.wordpress.com/2016/11/theil.jpg[/qimg]

Obviously a blog post is not the final word but I’d take this paper with a bigger grain of salt than normal until we have follow-ups.

I'll look through Tamino's posting, but this is not my take on the research that paper describes, but the writing is horrible and such often means that it takes a while to fully grasp such papers, as the authors defend their work from their peers the confusing areas should become more clear.

It sounded to me like they were saying that they were detecting a slow down in the rate of airborne anthropogenic emission residuals due to enhanced short-term sequestration focused primarily in boreal forest regions, and a reduction in the global respiration because warmer fall and winter temps in these regions are allowing plants to overwinter without having to shed most of their spring and summer growth and go dormant to survive winter temperatures.

From paper:
"... Overall, the impact of changes in climate on global net carbon uptake is uncertain, due to the small magnitude of the effect compared with differences between the DGVM models. It is worth noting however that there is a strong indirect effect of temperature through the alleviation of temperature limitations to growth in colder regions, and the extension of the growing season, observable as an increase in vegetation cover in satellite observations..."

Any "pause" seems more along the lines of looking at irrelevant variations over periods of time which are shorter than climatically significant periods (eg looking at decadal periods instead of triple-decade periods that are the minimal climate relevant time frame).

The paper itself doesn't suggest that their finding in anyway contradicts the primary understandings and findings of Climate science:

It is important to note that the land sink is due to the lag between carbon uptake through photosynthesis and release through respiration. Although the sensitivity of GPP to rising CO2 is expected to decline as CO2 concentrations rise (see Methods), the observed enhancement will thus likely persist into the future as long as the stimulation of productivity by elevated CO2 continues to outweigh net carbon releases from warming. The slowdown in global warming is expected to be temporary23 however and may already have ended with the strong El Niño Southern Oscillation of 2015 and 2016, with subsequent consequences for the growth rate of atmospheric CO2 (ref. 36). The likely continuation of warming in the coming decades37 suggests further future increases in net carbon releases.

I'm sure there are a lot of minor slow downs, and speed ups in these systems due to the complexity of the systems and the levels of forcings they are undergoing.

I'll go spend some time on Tamino's write-up, and see what he has to say.

 

[Trakar]

The extra is in the melting north and boreal forests, not in rain forests.

That was my impression as well.

 

[Trakar]

[qimg]http://www.nature.com/article-assets/npg/ncomms/2016/161108/ncomms13428/images/w926/ncomms13428-f1.jpg[/qimg]

[qimg]https://tamino.files.wordpress.com/2016/11/theil.jpg[/qimg]

Obviously a blog post is not the final word but I’d take this paper with a bigger grain of salt than normal until we have follow-ups.

One quick notice, it seems that Tamino has used global data, whereas the paper in question uses Terrestrial data (area over continental land masses) in their graph, which may account for the discrepancy between their graphs.

 

[macdoc]

Unknown unknowns ???....ouch....interesting times

The North Pole is an insane 36 degrees (20C) warmer than normal as winter descends
By Chris Mooney and Jason Samenow November 17 at 1:41 PM
Political people in the United States are watching the chaos in Washington in the moment. But some people in the science community are watching the chaos somewhere else — the Arctic.

It’s polar night there now — the sun isn’t rising in much of the Arctic. That’s when the Arctic is supposed to get super-cold, when the sea ice that covers the vast Arctic Ocean is supposed to grow and thicken.

But in fall of 2016 — which has been a zany year for the region, with multiple records set for low levels of monthly sea ice — something is totally off. The Arctic is super-hot, even as a vast area of cold polar air has been displaced over Siberia.

more ...good read
https://www.washingtonpost.com/news...al-as-winter-descends/?utm_term=.a98b3e1ca288

 

[Mr Clingford]

The Arctic has gone a bit odd, a bit melty, melty at this time of year.

 

[aleCcowaN]

LOL,...if only shame didn't require one to acknowledge culpability first!

It's a nation, not a person. That's why they talk of the collective unsconscious.

I think it'll be just shame with postponement, like the fatso who's always about to start her diet next Monday.

By the way, are we going for a third record breaking warmest year in a row? It looks that way in spite of the Niña.

I'm here taking refuge from the pampero (the Pampean Wind) for the second time in one month. It was a common event until the late 70s but it almost dissappeared later, I'm living an old fashion Spring during a pretty cold year. There were some slight frosts just a few days ago. Madness.


*no spell checker nor dicionaries, so any chain of words matching real English is a mere conicidence*

 

[Pixel42]

By the way, are we going for a third record breaking warmest year in a row? It looks that way in spite of the Niña.

It does indeed.

https://www.ncdc.noaa.gov/sotc/global/201610

With two months remaining, the 2016 year-to-date global temperature (January–October) was the highest for this period on record, at 0.97°C (1.75°F) above the 20th century average of 14.1°C (57.4°F). This value exceeds the previous record set in 2015 by 0.10°C (0.18°F).