Why exactly are we talking about paths for 'Getting to a 1.5C warming', when we've already hit 1.2C warming, and are still emitting more carbon each year than we have at any other point in our history?
Given the lag between carbon emissions and warming, and given the lag for introducing net emission reductions, how exactly are we expected to not blow right on past that 1.5C budget? Are we all going to permanently turn the lights off next week?
Avoidance of the worst impacts of climate change on agriculture.
If you're interested in hearing more about why we should be concerned about the stability of agriculture, consider looking at what happened to your grocery bill, just because a regional war broke out half a world away.
This is made somewhat more complex than might be immediately obvious as there is a huge amount of land which is too cold to be used for agriculture. Plants do not mind higher CO2 levels. It will cause dramatic chaos, don’t get me wrong, but it’s not clear the total amount of arable land will decrease.
>1.5 degrees is about the level of warming that scientists say would be more likely to start setting off irreversible feedback loops, such as the disintegration of ice sheets in Greenland and the West Antarctic, the abrupt thawing of permafrost in the Arctic, or the collapse of the Atlantic Ocean’s Gulf Stream current
That starts to happen at 1.5C and becomes really inevitable at 2C. The goal was to hold it to 1.5C to mitigate the worst of the damage.
Note that this is referring to when it gets above 1.5C every year. This paper doesn't predict that. It predicts that one year will be above 1.5C. That, in and of itself, is less relevant, except that it arrived a good decade or more sooner than expected. Which means that the consequences of permanently hitting 1.5C will also happen sooner.
Amusing side note: South Africa's power generation crisis contributed to it beating its CO2 emissions targets because their power stations aren't working.
Given the lag, we're already committed to 2.0C minimum. Thinking anything less is wishful thinking.
It doesn't really change anything. People will be putting up solar panels because it's cheaper than buying electricity from their utilities and run AC during sunny days when it's essentially free.
There is no chance that we will remain below 1.5C. Because there is (rightly) moral value attached to staying below 1.5, that fact is (also) hard to accept.
The formalized narrative makes sense through a values-based lens, as does the conversation moving through stages of grief as geophysics makes itself felt.
However, what it also demonstrates is that you can't reliably predict 'the next five years', what you see is that if you break up the global temperature trend into ten-year intervals, from one interval to the next you see this stepwise increase. The noise-to-signal ratio is such that it takes about ten years for climatic conditions to become noticeably different from the perspective of a human observer.
All we can really say at present is that the trend of extreme floods and droughts and heat waves and so on will be noticeably worse in 2033.
Incidentally, this is what the Earth looks like from space to an alien who evolved in a solar system where the Sun was much much redder - rather like Venus.
You can't see the planet's surface in IR, but the black spots are the cloud tops (if you look to the far right, you can see the daily Amazon jungle cloudburst cycle) - and the image is centered over the Pacific Ocean, which is reasonable, as it's hardly Planet Earth, at least not from the climate perspective - it's Planet Ocean. Temperature-wise, this means we won't see the planetary temperature stabilize for at least a century after fossil fuel emissions cease, due to the lag/buffering effect.
Don't get depressed, you get to live in interesting times!
> However, what it also demonstrates is that you can't reliably predict 'the next five years'
Generally, you can't, though I think in this case, the prediction is more confident due to the La Nina/El Nino phenomena.
Basically, the last few years have been breaking heat records despite a cooling force being in effect (La Nina). Now, that cooling force is gone and is replaced by a heating force (El Nino). So it's likely the fluctuations will now rather go up than down for the next few years.
I've been thinking a lot about how the https://en.wikipedia.org/wiki/Urban_heat_island effect of the sprawl of cities including the eastern seaboard of America could perhaps be effecting climate change.
The idea occurred to me after recently watching Twister and thinking why aren't we seeing more of these storms that I remember as a child were more frequent in the news.
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[ 3.0 ms ] story [ 78.5 ms ] threadWhy exactly are we talking about paths for 'Getting to a 1.5C warming', when we've already hit 1.2C warming, and are still emitting more carbon each year than we have at any other point in our history?
Given the lag between carbon emissions and warming, and given the lag for introducing net emission reductions, how exactly are we expected to not blow right on past that 1.5C budget? Are we all going to permanently turn the lights off next week?
https://www.theguardian.com/world/2023/may/01/private-jet-sa...
If you're interested in hearing more about why we should be concerned about the stability of agriculture, consider looking at what happened to your grocery bill, just because a regional war broke out half a world away.
Assuming you are in the US...there is very little agricultural import from a region half a world away.
And yet, I feel the price shocks nevertheless.
>1.5 degrees is about the level of warming that scientists say would be more likely to start setting off irreversible feedback loops, such as the disintegration of ice sheets in Greenland and the West Antarctic, the abrupt thawing of permafrost in the Arctic, or the collapse of the Atlantic Ocean’s Gulf Stream current
[0]: https://grist.org/science/el-nino-tipping-points-amazon-grea...
A bunch of coral reefs die at 1.5C. Not just die back and bleach, but dead-dead.
Shifts in the location of equatorial rains, which are especially important in agriculture in poor countries.
https://www.pnas.org/doi/10.1073/pnas.0705414105
That starts to happen at 1.5C and becomes really inevitable at 2C. The goal was to hold it to 1.5C to mitigate the worst of the damage.
Note that this is referring to when it gets above 1.5C every year. This paper doesn't predict that. It predicts that one year will be above 1.5C. That, in and of itself, is less relevant, except that it arrived a good decade or more sooner than expected. Which means that the consequences of permanently hitting 1.5C will also happen sooner.
https://businesstech.co.za/news/energy/688215/south-africa-u...
It doesn't really change anything. People will be putting up solar panels because it's cheaper than buying electricity from their utilities and run AC during sunny days when it's essentially free.
More likely we're going to be turning on a bunch of ACs and increasing our energy demands like we do every summer.
The formalized narrative makes sense through a values-based lens, as does the conversation moving through stages of grief as geophysics makes itself felt.
And the world hasn't ended, as it was broadcast to all of us when they were mentioning the 1.5C warming. We'll manage.
https://twitter.com/mathiasced/status/1616348855842250754?la...
However, what it also demonstrates is that you can't reliably predict 'the next five years', what you see is that if you break up the global temperature trend into ten-year intervals, from one interval to the next you see this stepwise increase. The noise-to-signal ratio is such that it takes about ten years for climatic conditions to become noticeably different from the perspective of a human observer.
All we can really say at present is that the trend of extreme floods and droughts and heat waves and so on will be noticeably worse in 2033.
Incidentally, this is what the Earth looks like from space to an alien who evolved in a solar system where the Sun was much much redder - rather like Venus.
https://youtu.be/f7QttjGu628
You can't see the planet's surface in IR, but the black spots are the cloud tops (if you look to the far right, you can see the daily Amazon jungle cloudburst cycle) - and the image is centered over the Pacific Ocean, which is reasonable, as it's hardly Planet Earth, at least not from the climate perspective - it's Planet Ocean. Temperature-wise, this means we won't see the planetary temperature stabilize for at least a century after fossil fuel emissions cease, due to the lag/buffering effect.
Don't get depressed, you get to live in interesting times!
Staircase looks a lot less exciting here: https://149366104.v2.pressablecdn.com/wp-content/uploads/202...
https://en.wikipedia.org/wiki/UAH_satellite_temperature_data...
https://en.wikipedia.org/wiki/Microwave_Sounding_Unit_temper...
Generally, you can't, though I think in this case, the prediction is more confident due to the La Nina/El Nino phenomena.
Basically, the last few years have been breaking heat records despite a cooling force being in effect (La Nina). Now, that cooling force is gone and is replaced by a heating force (El Nino). So it's likely the fluctuations will now rather go up than down for the next few years.
The idea occurred to me after recently watching Twister and thinking why aren't we seeing more of these storms that I remember as a child were more frequent in the news.
https://www.climate.gov/maps-data/dataset/monthly-and-annual...
Number of tornados per year has been increasing, on average. Just because you aren't paying attention doesn't mean it's not happening.
Given that classification is therefore perhaps not consistent, lets see the numbers of big tornados... https://www.wunderground.com/cat6/an-historical-look-at-f5-e...
1. https://news.umich.edu/climate-change-and-michigan-challenge...
Still >6C colder than 20 million years ago.