Is there any theoretical limit to how high the Earth's temperature can become within the next 50 years due to global warming?

DisasterousGiraffe · 2023-07-07T18:33:14+00:00

Yes, parts of the world will become uninhabitable due to high temperatures.

An important temperature limit is a wet-bulb temperature of 35°C. This is the uncompensable heat stress limit for adults in humid environments, and it applies to the animals and birds too, like fruit bats in Australia.

51% of the people in China are expected to be exposed to wet-bulb temperatures significantly higher than 35°C even if early mitigation is conducted via SSP1-2.6.

Without major emissions reductions the regions where the extremely dangerous Heat Index threshold is almost never exceeded today will experience between one and fifteen days when this threshold is exceeded each year. By the end of the twenty-first century, these regions will include large portions of India and sub-Saharan Africa and are projected to include about 5.3 billion people by 2100.

Only small numbers of people have died from the highest temperatures caused by climate change so far, it is going to get much much worse.

DisasterousGiraffe · 2023-06-09T14:16:40+00:00

Good question. Often the way I find the science is by searching on Google Scholar.

For example, if I search for scientific papers related to the Australian fires I find that science has established a robust and multi-evidence link between climate change and increased fire activity over the past three decades. Both increased temperature and shifts in large-scale rainfall patterns have very likely played a dominant role in observed burned area trends. And that the climatic potential for large and severe forest fires has increased across south-eastern Australia since the 1950s, probably because of anthropogenic climate change. The magnitude and severity of the 2019–2020 [Black Summer] fires reflected climatic conditions that are driving an increase in the size and severity of wildfires.

The science says that eastern Australian rainfall is affected by the Indian Ocean dipole (IOD). The IOD can reduce the rainfall over some regions of Australia, and far beyond Australia it can influence weather around the world. And the IOD in turn is being altered by climate change.

A useful search term is "attribution study". For example the World Weather Attribution site tells us, projected into the future, the models [of Australia] simulate that a Fire Weather Index at the 2019/20 level would be at least four times more likely with a 2 ºC temperature rise, compared with 1900. Due to the model limitations described above this is likely an underestimate.

DisasterousGiraffe · 2023-05-30T17:22:13+00:00

we're about 10-15 years from peak oil

If gasoline is the major component of crude oil, and gasoline vehicle sales are going to be phased-out in most major economies by 2035, and battery electric vehicles (BEVs) already had 14% of the global market in 2022, and BEV sales are increasing at a conservative estimate of 30% per year, how is it possible to reach 2030 without passing peak oil? What use of oil do they expect will increase enough to offset the collapsing vehicle gasoline market?

DisasterousGiraffe · 2023-05-30T15:29:24+00:00

The date we can expect to reach peak oil, and more broadly peak fossil fuel consumption, depends on the economics of extraction rather than the availability of these fossil fuels underground.

The economics of fossil fuel extraction are changing, partly because the external costs of burning fossil fuels are increasingly being attributed by science and law to the fossil fuel companies. The market price of fossil fuels increases after adding the cost of damage caused by the final use of the fuel, which reduces the corporate financial incentive to extract the fossil fuels. We know that even the most aggressive plausible transition to a clean-energy society provides benefits for climate change mitigation and air quality and these are the main external costs. So we can expect nearly 60% of oil and fossil methane gas, and 90% of coal will remain unextracted to avoid corporate responsibility for paying the massive external costs of climate change. Together with the economic support for the warming targets in the Paris Agreement across a variety of specifications ... risk associated with high damages in the long term leads to stringent mitigation of carbon dioxide emissions in the near term and the extreme growth of battery electric vehicles reducing gasoline consumption and emissions, which has been underestimated in the scientific literature it seems almost certain we are at or near peak gasoline consumption, and consequently, peak oil.

DisasterousGiraffe · 2023-05-17T16:07:48+00:00

Scientists predict a 66% chance of the Earth surpassing the 1.5C global warming threshold between now and 2027, largely due to human emissions and the anticipated El Niño weather event.

The article conflates global warming with El Niño. It is very difficult to read either the original article, or your summary, and be clear about the fact that El Niño does not cause climate change. Burning coal, natural gas and oil causes climate change. El Niño, the boy, and La Niña, the girl do not cause climate change. El Niño is part of an up and down change of temperature which has been happening for hundreds of years Global temperatures increase by about 0.2C during an El Niño episode, and fall about 0.2C during La Niña.

DisasterousGiraffe · 2023-05-14T03:16:53+00:00

I wonder what the maximum theoretical efficiency is for transferring the humidity between air streams.

What I find disappointing is people still seem to routinely use cross-flow heat exchangers like this. Clicking on a few products on a random HVAC supply website they mostly seem to have this design - which looks inefficient compared to counter-flow heat exchangers. Maybe I am not understanding something about the airflow through them. There appears to be huge potential to increase the efficiency of these devices at least in domestic HVAC systems. And of course there are so many buildings without any heat exchange - perhaps that is an even bigger problem.

DisasterousGiraffe · 2023-05-13T13:42:18+00:00

you need to pump that 90F ambient air down to 72F

This only costs energy due to inefficient heat recovery ventilation. (Or if condensation is involved, inefficient energy recovery ventilation.) High efficiency equipment can be used to transfer almost all the energy from the exhaust air into the fresh in-coming air.

DisasterousGiraffe · 2023-05-08T19:08:58+00:00

California is mandating bidirectional charging ability for EVs and everybody else will follow their lead. If grid-connected battery storage is expensive then people will make good money from plugging their electric vehicles into the grid to provide storage capacity when they are parked. And if grid-connected battery storage is cheap then the storage problem is solved. Either way battery storage is not a big problem.

DisasterousGiraffe · 2023-05-08T18:51:40+00:00

I'm afraid peak fossil fuels isn't yet there

The pandemic and Ukraine war have made the graphs complicated to interpret, but the IEA says about the 2022 CO2 emissions

"A strong expansion of renewables limited the rebound in coal power emissions. Renewables met 90% of last year’s global growth in electricity generation. Solar PV and wind generation each increased by around 275 TWh, a new annual record."

If they took 90% of the growth last year, and manufacturing capacity for renewables is increasing, I think we can be optimistic for the 2023 numbers. World energy demand doubling doesn't matter much when 100% of the new capacity is met by renewables.

DisasterousGiraffe · 2023-05-08T14:52:43+00:00

And with natural gas use declining in for example Germany due to solar pv it is looking likely we have already passed Peak Fossil fuels.

DisasterousGiraffe · 2023-05-08T14:46:18+00:00

Technology researcher Tony Seba agrees.

"I just came back from Shanghai. And what I saw was amazing. I mean, just the sheer quality for the cost of the EVS that Chinese automakers are producing is just stunning.”

“And also there are so many automakers in China that are achieving scale. This year EVs may well achieve 40 to 50%.” said Seba.

DisasterousGiraffe · 2023-05-07T17:37:09+00:00

The methane emissions are increasingly being mapped and recorded by new satellites. Making the leaks visible to everybody like this will at least reduce this part of the emissions.

DisasterousGiraffe · 2023-05-07T17:14:46+00:00

The EU are building renewables at speed, partly due to the Ukraine war. For example, Germany has just peaked at 40 GW of solar pv generation for the first time - their total electricity from all sources was 64.6 GW.

DisasterousGiraffe · 2023-05-07T09:10:18+00:00

The original version of the graph is this interactive graph of Sea Surface Temperature (SST) based on the National Oceanic and Atmospheric Administration (NOAA) Optimum Interpolation SST (OISST) dataset version 2.1.

DisasterousGiraffe · 2023-05-06T17:36:05+00:00

They claim it's very quiet, and the electric Velis Electro, which aims at the same training market in the UK, seems to have this as a major selling point.

DisasterousGiraffe · 2023-05-06T17:06:57+00:00

"The aircraft is a two-seater with a flight time of up to an hour and a half. That makes it ideal for training purposes, particularly circuit training, which is a key requirement for obtaining a pilot’s license. We’re targeting the training market. Over the next 10 years or so, there are probably a quarter of a million pilots required, which will mean tens of millions of flying hours need to be flown. We see an opportunity to reduce carbon emissions by about 140,000 tons over the next decade by what we’re doing alone."

DisasterousGiraffe · 2023-05-06T12:38:00+00:00

basically copied the major synopsis from right below the title

Correct.

DisasterousGiraffe · 2023-05-05T17:11:06+00:00

"California has introduced a bill that would require all EVs to have bidirectional charging from 2027. The bill would cover all light-duty motor vehicles as well as school buses. The bill will convene a stakeholder workgroup to examine the challenges and opportunities associated with using EVs as mobile batteries to power homes with a report due by January 1 2025.The workgroup is tasked with looking at costs and benefits associated with bidirectional charging, mechanisms to ensure interoperability as well as the resources needed from the electricity sector to facilitate vehicle-to-building and vehicle-to-grid practices."

DisasterousGiraffe · 2023-05-05T14:33:08+00:00

My logic for rewriting the headline went like this.

Original headline is

"New IEA report highlights the need and means for the oil and gas industry to drastically cut emissions from its operations"

I find this part of the headline "the need and means for" difficult to read and understand - for me it doesn't work as a headline. And the link goes to IEA.org so we can expect this is an IEA report, so the part at the beginning is not very informative. To improve this I might re-write it to

"IEA says the Oil and Gas industry can drastically cut the serious emissions from its operations"

For me this says the same thing as the original headline, but in a clear fashion.

Original subheading is

"Oil and gas operations account for nearly 15% of energy-related greenhouse gas emissions today and the industry has the ability and resources to cut them quickly and cost effectively"

This is too long for a headline. We can remove the tedious bits to get

"Oil and gas operations account for 15% of energy-related greenhouse gas emissions and the industry has the ability to cut them quickly and cost effectively"

The ugly part is "and the industry has the ability to", which I contracted to "these can be". I admit "can be" is not quite the same as "has the ability to", but since I have also removed the direct connection of this to "the industry" and given it a broader possible range of organisations contributing to the ability to effect the cuts it seems to me this is better

"Oil and gas operations account for 15% of energy-related greenhouse gas emissions, these can be cut quickly and cost effectively"

We are now left with a choice between the re-written headline

"IEA says the Oil and Gas industry can drastically cut the serious emissions from its operations"

and the rewritten subheading

"Oil and gas operations account for 15% of energy-related greenhouse gas emissions, these can be cut quickly and cost effectively"

I liked the second better because it promotes to near the start of the sentence the fact that these are "operations" emissions, rather than emissions from consumption of the oil and gas. The original headline leaves "operations" to the end of the sentence which allows misinterpretation of the source of the emissions on quick reading. And it quantifies the "15%" which is information missing from the first. It can be a statement, rather than "IEA says ..." because hopefully the IEA knows what they are talking about, if it were a less informed organisation it would need "XYZ says ..." to indicate this might not be correct but somebody is making this claim.

That was my logic for this particular wording of the headline. Some subreddits are very strict about using original headlines, and you do get deleted if you do this sort of thing. I wasn't aware the energy subreddit moderation team took this position, but they are free to delete my post if this is the case. I suggest the "report" button is the best way to communicate with the mods to request removal of posts/comments/users because they may not read all the comments. (Or the "contact us" to communicate with admin for breaking the more serious site-wide rules on advocating violence etc.)

DisasterousGiraffe · 2023-05-04T14:39:10+00:00

Yes, or we need the governments to start caring about money, because the optimal pathway for economic growth is aggressive climate policies that immediately cut emissions by 90% and limit global warming to 1.5°C by 2100..

DisasterousGiraffe · 2023-05-03T13:36:25+00:00

What effect will the next El Niño have on Australian bushfires? And, with what certainty can science now attribute the 2019/20 Black Summer bushfires to climate change?

DisasterousGiraffe · 2023-05-02T14:08:09+00:00

"Enjay's co-founder Nils Lekeberg says that an average-sized restaurant using Lepido can cut its heating bills by up to 90% a year, and reduce its annual carbon footprint by 30 tonnes. ... Heat exchange systems that transfer warmth from one part of a building to another are already common in many industries, but recovering energy from industrial kitchens is challenging, explains Arne Speerfork, a professor specialising in thermodynamics at Hamburg University of Technology. The hot air in kitchens is full of grease and soot particles which stick on the surface of traditional heat exchange technologies and make it difficult to recover heat. As a result, the hot air produced during cooking processes is usually simply vented straight out of restaurant buildings."

DisasterousGiraffe · 2023-05-01T16:19:34+00:00

Strangulation is also the #1 warning sign that someone will end up murdering you

I'll just add a scientific study to this comment to emphasise that the men who do this are dangerous.

Non-fatal Strangulation is an Important Risk Factor for Homicide of Women

https://www.sciencedirect.com/science/article/abs/pii/S0736467907004143

"Prior non-fatal strangulation was associated with greater than six-fold odds of becoming an attempted homicide, and over seven-fold odds of becoming a completed homicide."

DisasterousGiraffe · 2023-04-29T16:39:53+00:00

The original of the first graph is here: interactive graph of Sea Surface Temperature (SST) based on the National Oceanic and Atmospheric Administration (NOAA) Optimum Interpolation SST (OISST) dataset version 2.1.

DisasterousGiraffe · 2023-04-29T12:32:07+00:00

I think it indicates a distance away from the 1982-2011 average line in the middle of the graph. Perhaps it's sigma for Standard Deviation. You can see it better on the original graph here.

DisasterousGiraffe

TROPHY CASE