What’s the problem with producing CO2 emissions. That is the question that is continually dodged, or answered by innuendo and presumptions, but not with valid evidence.
Note, in case anyone is confused, temperature change is neither good not bad. Only the impacts of the change might be good or bad.The assessment of total benefit or damage must be for the world economy in either percent GDP change, or net economic benefits minus costs, caused by global temperature change.
This almost amounts to a roundabout “science court.”
Jack: there was a time when the ‘embodied emissions’ claim was powerful. No longer. The 2014 consumption-based figures can be found here: http://www.globalcarbonproject.org/carbonbudget/16/files/GCP_CarbonBudget_2016.pdf Note how, even from that perspective, China is still responsible for by far the highest percentage of global emissions. In any case, these figures include goods etc. the developing countries export to each other. The reality is that the world has changed radically over recent years: today China is a massive consumer-led economy.
“how could the US be held responsible to the plaintiffs when other countries are emitting 86% of GHGs?”
Probably they’ll say the U.S. is at fault indirectly, for withdrawing from the Paris accord.
They might try. But it wouldn’t affect the argument that the US emits (and will continue to emit) only a small proportion of global emissions – especially as the Paris Agreement lets the developing countries, responsible for over 65% of emissions, entirely off the emission reduction hook.
This repeating cycle of 100,000-year glaciations and 10,000 to 20,000 year interglacials has been fairly consistent over the past 2.6 million years. ~Mario Loyola (“Twilight of the Climate Change Movement”)
“A “proxy” is a type of measurement which can be used to indirectly approximate some property – in this case, Arctic sea ice cover.”
Jeez, I had never made the connection with proxy and approximate.
I subconsciously assumed that “proxy’ was more sciency and less approximating.
Thanks for this work, especially since I’ve been forced flee the news media and reduced to reading only climate stuff.
You guys realize that Spiraling Arctic Ice Death Without Resurrection is the core tenet of the religion and you will be branded heretics, if that hasn’t already happened.
Tenure?
The same breakpoints are evident in hydrological datasets across the planet – for reasons that are understood by any with the requisite intellectual tools. The breakpoints are an emergent behaviour of globally coupled chaotic oscillators in the spatio-temporal chaos of the Earth system.
“Yet even in the general case it appears completely clearly that the system doesn’t follow any dynamics of the kind “trend + noise” but on the contrary presents sharp breaks , pseudoperiodic oscillations and shifts at all time scales. Of course the behaviours in the case when the coupling constants vary will be much more complicated and are not studied in the paper.
Unfortunately people working on these problems are not interested by the climate science and those working in climate science are not even aware that such questions exist , let alone have adequate training and tools to deal with them.” Tomas Milanovic
Tomas was being a little unfair – there are no tools for the infinitely dimensioned coupling of the spatio-temporal chaos of the climate system. Ab alternative to a math that may or may not develop over coming decades is network techniques.
“Considering index networks rather than raw three-dimensional climate fields is a relatively novel approach, with advantages of increased dynamical interpretability, increased signal-to-noise ratio, and enhanced statistical significance, albeit at the expense of phenomenological completeness.” Marcia Wyatt
Tsonis and colleagues identified the climactically important 20 to 30 year breakpoints in the 20th century using network math and 4 NH ocean and atmospheric indices. Breaks occurred around 1912, the mid 1940’s, the late 1970’s and the late 1990’s. It is a simple coincidence that the break in the 1970’s involving in part a shift in the Pacific Ocean state occurred at the start of the satellite era.
http://onlinelibrary.wiley.com/doi/10.1029/2007GL030288/abstract
Tessa Vance and colleagues identified the 20 to 30 year regimes in a high resolution millennial ENSO proxy from a Law Dome ice core – but also variability that mirrors variability of cosmogenic isotopes over a 1000 years. Both the shift to high intensity El Nino and the change in the ENSO beat in the early 20th century suggests that we should be looking for a solar origin of stochastic ENSO forcing that varies with about a 20 to 30 year scale.
http://journals.ametsoc.org/doi/abs/10.1175/JCLI-D-12-00003.1
More salt in the ice core is La Nina and more generally a cool Pacific state – and more rain in Australia. My hypothesis is that solar UV/ozone chemistry modulate surface pressure at the poles – e.g. http://iopscience.iop.org/article/10.1088/1748-9326/11/3/034015/meta – and this influences the evolution of the the polar annular modes. There are many of these studies emerging but typically they focus on the NH and reject any global implications on the basis of that shuffling energy around the NH doesn’t amount to changes in the global energy budget. I tend to agree – but it also reinforces Tomas’ view of a lack of perspective in climate science.
Working backwards may help. There are both satellite and surface observation of cloud – with a significant impact on energy dynamics at toa – in the eastern Pacific that is anti-correlated with sea surface temperature. Sea surface temperature there varies substantially with the volume of upwelling. Upwelling is related to flows in the Peruvian and Californian current which in turn is influenced by the polar annualr modes – so we come full circle. This is an extreme simplification of the spatio-temporal chaos of the Earth system -but it does involve physical mechanisms – including catastrophe theory as there is no simple cause and effect – in a major mode of climate variability.
Any plans to make a grided sea ice reconstruction? A time series of ice extent is useful, but grided sea ice data would be even more useful.
“and they seem to drastically underestimate the natural sea ice variability”
Don’t you think it’s unfair to make this claim based on a comparison with the CMIP5 multimodel mean? Wouldn’t it make more sense to look at the variability within each individual run?
Excellent hydrological paper btw.
Well, they have but you don’t want to believe it yet.
It might be tariffs rather than boycotts.
The skeptics have yet to express why they think a 700 ppm climate is better or at least not worse than a 400 ppm climate. That is where they should make their case, but no one shows up when I ask that.
I’ve been updating this figure for the past 2 years and will update it again next October.
It shows Cea Pirón & Cano Pasalodos 2016 reconstruction of September sea ice extent from 1935 to 1978 based on previous databases including the Russian data. The reconstruction is overlaid over the IPCC prediction based on different emission scenarios, with the essentially ice-free condition of less than 1 million sq. km.
Already the early melting alarmist predictions based on an exponential decay from 2007-2012 values has been shown incorrect. If the AMO relationship defended in Miles et al., 2014 and Wyatt & Curry, 2014 is correct we should not see any significant melting until at least 2030-40, By then we should be able to dismiss IPCC projections as excessively pessimistic.
The AMO relationship is based on the similar behavior of both AMO and Arctic ice, and does not imply a causal relationship, as both could be responding to the same changes and be in the same “Stadium wave” position.
a linear trend in temperature or sea ice after removing AMO doesn’t make any sense. Forcing changes have been non-linear, and there is a delayed response to forcing.
Arctic sea ice shows an integrative response to multiple factors, some of which are chaotic, like weather associated storms.
As we can see from the behavior of the past 10 years Arctic sea ice does not respond primarily to GSAT.
https://wattsupwiththat.com/2017/08/11/arctic-melt-season-changes-and-the-arctic-regime-shift
It also doesn’t depend primarily on the length of the melt season.
However all these factors and more can affect Arctic sea ice extent. But the primary factor is a different one. We can speculate that it is probably Arctic water temperatures. Water temperatures and pressure are linked, so it is not surprising that AMO and Arctic sea ice share stages and trends.
Since the world has been warming for the past 400 years a general multicentury trend towards less sea ice would also not be surprising. If the world was cooling, after removing every other factor, a linear trend towards more ice would also fit the data.
Whether true or not, the situation presented is consistent with the available evidence, and defended in several articles.
But only 14,000 years delayed response:
http://euanmearns.com/the-vostok-ice-core-and-the-14000-year-co2-time-lag/
RIE, I was referring to the ocean temperature, of course. I will requote myself because it now looks like you misunderstood right from the beginning.
“Put numbers in and you find that the ocean temperature change you showed requires 1 W/m2 to be sustained to warm it at that rate. Your SW wiggles are nothing like that, so you have to look beyond the clouds to some background forcing imbalance, like the well known one from GHGs, for example.”
