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Policy and solutions / Re: Renewable Energy
« Last post by interstitial on Today at 12:44:10 AM »
A major wind tax credit was set to expire at the end of 2020. In December it was extended. Unfortunately it probably wont help 2021 wind installations.
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The US is back in.

https://www.npr.org/sections/inauguration-day-live-updates/2021/01/20/958923821/biden-moves-to-have-u-s-rejoin-climate-accord

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Biden Moves To Have U.S. Rejoin Climate Accord

January 20, 2021

In one of his first acts in the Oval Office, President Joe Biden signed an executive order to have the United States rejoin the Paris climate agreement, the largest international effort to curb global warming.

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It will take 30 days for the U.S. to officially rejoin the agreement, but meeting its targets is going to be a taller order. The U.S. is the second-largest producer of carbon emissions, behind China, and has contributed more to global climate change over time than any other country.

As a candidate, Biden made a bold pledge to cut all greenhouse gas emissions from the nation's electric sector by 2035 and to make the country carbon-neutral by 2050. Carbon emissions have been decreasing from the country's electricity sector as coal plants have been retired over the last decade and utilities ramp up their reliance on renewable energy sources like wind and solar.
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The politics / Re: Biden’s Presidency
« Last post by sidd on Today at 12:30:04 AM »
Two good things: Biden extends eviction moratorium unti March, pause on student loan payments until September.

https://www.politico.com/news/2021/01/21/joe-biden-executive-action-blitz-day-one-460587

buncha other stuff in there too. Those caught my eye because i really hate to see people getting thrown out midwinter. And student loan terms are obscene to begin with.

sidd
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Science / Re: Global Warming Would Stop Quickly After Emissions Go To Zero
« Last post by sidd on Today at 12:23:24 AM »
Coal India, one of the largest coal producers in the world plans 20 GW of solar. They know whats coming.

https://www.moneycontrol.com/news/business/coal-india-sets-20-gw-solar-power-generation-target-in-next-10-years-2540315.html


sidd
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Quote
Global concentrations of Carbon Dioxide are averaging about 412 ppm, which is in line with the RCP 2.6 scenario.  RCP 8.5 would have the 2020 global average at 415 ppm.
Ken, what counts is CO2eq which is well above 415 ppm. And the main negative force, aerosols, is gonna go down fast if we transition to renewable.

This misunderstanding about CO2eq often pops up on this forum.  CO2eq is a way to take all of the greenhouse gas forcings and combine them into one number.  The IPCC reports take the concentrations of each greenhouse gas and add their forcings.  This is what I showed in the IPCC chart with the individual forcings graphed.

Spikes in temperature due to the decrease of aerosols from the reductions of fossil fuel power sources have been demonstrated to be false.

https://www.carbonbrief.org/cutting-air-pollution-would-not-cause-near-term-spike-in-global-warming

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18 September 2019
Cutting air pollution would not cause ‘near-term spike’ in global warming

A reduction in air pollution brought about by shifting away from fossil fuels would not inadvertently cause a short-term acceleration of global warming, a new study says.

Earlier modelling work using scenarios where fossil-fuel burning ends instantaneously had suggested that a rapid decline in aerosol emissions could remove their cooling impact on the climate and cause a spike in warming.

However, the new study, published in Nature, finds that “even the most aggressive” shift from fossil fuels to clean alternatives to limit warming to 1.5C “provides benefits for climate change mitigation and air quality” at all timescales.

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However, there is a key limitation with these studies, says Smith, in that they typically assume an instantaneous removal of all emissions. This is not “realistic in our complex, interdependent world”, he says, which would take much longer to phase out fossil fuels.

In the fifth assessment report of the Intergovernmental Panel on Climate Change (IPCC), for example, “frequently asked question 12.3” (pdf) states that “eliminating short-lived negative forcings from sulphate aerosols at the same time (e.g. by air pollution reduction measures) would cause a temporary warming of a few tenths of a degree”.

The accompanying figure (see below) showed this spike in global surface warming (blue dotted line) compared to constant emissions (red) and if the atmospheric concentration of greenhouse gases was held constant at present-day levels (grey).



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The model simulations show that, even under the most rapid transition away from fossil fuels, “it takes a good deal of time to actually move the entire planet’s energy systems to clean energy”, says lead author Prof Drew Shindell, professor of earth sciences at Duke University.

The results suggest that, under these more realistic scenarios, “global average temperatures do not show a near-term spike in warming”, the paper says.

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While the scenarios show some continued warming in the near term, “none exhibit an acceleration of warming to 0.3C or higher’, the paper says, and “all show a rapid decline in warming rates starting in the 2020s” with some showing cooling by the 2040.

Here's the study referred to in the article:

https://www.nature.com/articles/s41586-019-1554-z#citeas

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Shindell, D., Smith, C.J. Climate and air-quality benefits of a realistic phase-out of fossil fuels. Nature 573, 408–411 (2019). https://doi.org/10.1038/s41586-019-1554-z

Abstract

The combustion of fossil fuels produces emissions of the long-lived greenhouse gas carbon dioxide and of short-lived pollutants, including sulfur dioxide, that contribute to the formation of atmospheric aerosols1. Atmospheric aerosols can cool the climate, masking some of the warming effect that results from the emission of greenhouse gases1. However, aerosol particulates are highly toxic when inhaled, leading to millions of premature deaths per year2,3. The phasing out of unabated fossil-fuel combustion will therefore provide health benefits, but will also reduce the extent to which the warming induced by greenhouse gases is masked by aerosols. Because aerosol levels respond much more rapidly to changes in emissions relative to carbon dioxide, large near-term increases in the magnitude and rate of climate warming are predicted in many idealized studies that typically assume an instantaneous removal of all anthropogenic or fossil-fuel-related emissions1,4,5,6,7,8,9. Here we show that more realistic modelling scenarios do not produce a substantial near-term increase in either the magnitude or the rate of warming, and in fact can lead to a decrease in warming rates within two decades of the start of the fossil-fuel phase-out. Accounting for the time required to transform power generation, industry and transportation leads to gradually increasing and largely offsetting climate impacts of carbon dioxide and sulfur dioxide, with the rate of warming further slowed by reductions in fossil-methane emissions. Our results indicate that even the most aggressive plausible transition to a clean-energy society provides benefits for climate change mitigation and air quality at essentially all decadal to centennial timescales.


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A somewhat heavy GIF but I hope it is worthy.  Frames are from here: https://acd-ext.gsfc.nasa.gov/Data_services/met/qbo/anim.html

New type of wave seems to be crashing in it.  The QBO is fairly powerful... heads up





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Science / Re: Global Warming Would Stop Quickly After Emissions Go To Zero
« Last post by ArgonneForest on January 20, 2021, 11:45:19 PM »
I gave evidence regarding coal and India, which you then chose to completely disregard. Also, you and Blu Ice trotted out the same crappy talking points to basically say nothing has been done and the world is doomed. Neither of which is true I might add. You must have fallen asleep while renewables surged globally, the EU agreed to more stringent targets, and Biden put out an aggressive climate plan.
Maybe look up the concept of reconciliation in the Senate before shooting your mouth off about what Dems can or can't do. Also, try keeping up with renewables development in China: https://mobile.twitter.com/laurimyllyvirta/status/1351916159642324994

I am pleased to see someone else argue optimistically that BAU has changed dramatically. Too many around here believe in climate catastrophe is imminent. However saying they "completely disregarded" what you said when in fact what they did was point out that electricity grid is only part of our energy usage. This comes across as you ignoring them not them ignoring you.

Heating homes is much tougher than electricity. Heat pumps seem much more expensive than a ff boiler. Maybe they will get cheaper with volume, that has worked brilliantly with wind and solar electric but I am not sure we can rely on that again.

So I think you and I should admit they have a point. Yes electric is not all of our ff use but BAU has changed dramatically. Of course it would be better for climate if we did more and I want us to do more. However the economic case of being less expensive to do things about climate than suffer the consequences was based on BAU scenarios that are now clearly way off what we should expect and obviously had way worse climate outcomes under the assumed BAU which made action to avoid the worst look cheap. Now we know BAU has changed dramatically the economic case needs to be re-examined and made again.

 

Well-said, Crandles. Much more needs to be done, for sure. That being said, if Biden can get his plan through the Senate (it will sail through the House), then it would be an excellent start
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Science / Re: Global Warming Would Stop Quickly After Emissions Go To Zero
« Last post by Ken Feldman on January 20, 2021, 11:39:57 PM »
There are many incorrect assumptions being made about the science and impacts of climate change on this thread.  These often lead to people concluding that we are already doomed, when it is quite clear that the situation has improved dramatically in the past two years and we can limit global warming to well under 2 degrees C.

One of the reasons to keep the temperature increase well under 2 degrees C is that the incidences of loss of the Arctic sea ice decrease from about once per decade at 2 C versus once per century at 1.5 C.

https://www.ipcc.ch/sr15/

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The probability of a sea-ice-free Arctic Ocean5  during summer is substantially higher at 2°C compared to 1.5°C of global warming (medium confidence). Model simulations suggest that at least one sea-ice-free Arctic summer is expected every 10 years for global warming of 2°C, with the frequency decreasing to one sea-ice-free Arctic summer every 100 years under 1.5°C (medium confidence). An intermediate temperature overshoot will have no long- term consequences for Arctic sea ice coverage, and hysteresis is not expected (high confidence). {3.3.8, 3.4.4.7}

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A substantial number of pre-AR5 studies found that there is no indication of hysteresis behaviour of Arctic sea ice under decreasing temperatures following a possible overshoot of a long-term temperature target (Holland et al., 2006; Schröder and Connolley, 2007; Armour et al., 2011; Sedláček et al., 2011; Tietsche et al., 2011; Boucher et al., 2012; Ridley et al., 2012). In particular, the relationship between Arctic sea ice coverage and GMST was found to be indistinguishable between a warming scenario and a cooling scenario. These results have been confirmed by post-AR5 studies (Li et al., 2013; Jahn, 2018), which implies high confidence that an intermediate temperature overshoot has no long-term consequences for Arctic sea ice coverage.

The Jahn, 2018 study addresses both the probabilities of ice-free states and whether they're reversible.

https://www.nature.com/articles/s41558-018-0127-8

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Jahn, A. Reduced probability of ice-free summers for 1.5 °C compared to 2 °C warming. Nature Clim Change 8, 409–413 (2018). https://doi.org/10.1038/s41558-018-0127-8

Abstract

Arctic sea ice has declined rapidly with increasing global temperatures. However, it is largely unknown how Arctic summer sea-ice impacts would vary under the 1.5 °C Paris target compared to scenarios with greater warming. Using the Community Earth System Model, I show that constraining warming to 1.5 °C rather than 2.0 °C reduces the probability of any summer ice-free conditions by 2100 from 100% to 30%. It also reduces the late-century probability of an ice cover below the 2012 record minimum from 98% to 55%. For warming above 2 °C, frequent ice-free conditions can be expected, potentially for several months per year. Although sea-ice loss is generally reversible for decreasing temperatures, sea ice will only recover to current conditions if atmospheric CO2 is reduced below present-day concentrations. Due to model biases, these results provide a lower bound on summer sea-ice impacts, but clearly demonstrate the benefits of constraining warming to 1.5 °C.
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Science / Re: Global Warming Would Stop Quickly After Emissions Go To Zero
« Last post by RoxTheGeologist on January 20, 2021, 11:35:16 PM »
“Renewables will play an increasingly important role, with their share of the overall energy mix rising to 15% in 2040,” the AMP Capital report says.

https://www.ampcapital.com/content/dam/capital/04-articles/insto-edition/2019/012020%20Energy%20Infra%20Whitepaper_Spreads.pdf

We need far more wide-reaching changes than are happening now.
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The politics / Re: The Trump Presidency
« Last post by karl dubhe2 on January 20, 2021, 11:28:03 PM »
Thank the non-existent god it's over.

Except for the lawsuits and the criminal cases.   :D :D :D
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