This shouldn't surprise anyone, but the conclusion of the paper doesn't support the headline.
>This comparison suggests that the likely upper level of sea level projections in recent IPCC reports would be too low.
The onclusion:
>We compare the model projections over the 21st century assessed by the IPCC with historical records from 1850–2017. We find that the model projections assessed in both AR5 and SROCC fall substantially below an extrapolation of historical records (Fig. 2). ....
>Taken together this suggests that the projected global sea level rise by the end of this century in various IPCC reports is at best conservative and consequently underestimates the upper bound of what is referred to as the likely sea level rise by the end of this century.
If you are asking for empirical data from the future, you are asking for time travel.
"Taken together this suggests that the projected global sea level rise by the end of this century in various IPCC reports is at best conservative and consequently underestimates the upper bound of what is referred to as the likely sea level rise by the end of this century."
(a) Who can tell what can happen "by the end of this century"? That's too far in the future.
(b) We have time, we can sort it out till then.
(c) I'll be dead, and more likely than not my kids will be too, 80 years from now.
This argument sounds sort of frivolous, but it is actually quite strong.
If the climate was radically different 100 years ago, how many people would care, or even know?
We in Canada or the United Kingdom might not notice, but I'm pretty sure those in Texas or Nigeria will.
Is Texas or Nigeria the warmest places people live atm though?
The wet bulb temperature is the thing to watch:
> A sustained wet-bulb temperature exceeding 35 °C (95 °F) is likely to be fatal even to fit and healthy people, unclothed in the shade next to a fan; at this temperature our bodies switch from shedding heat to the environment, to gaining heat from it.[9] Thus 35 °C (95 °F) is the threshold beyond which the body is no longer able to adequately cool itself. A study by NOAA from 2013 concluded that heat stress will reduce labor capacity considerably under current emissions scenarios.[10] - https://en.wikipedia.org/wiki/Wet-bulb_temperature
Far north places like Scandinavia and Canada might actually benefit a little bit by being able to grow crops that they currently can't due to their harsh winters and cold nights all over the year! But their southern neighbours will surely suffer a lot, and that's where most of the population currently is.
https://www.scientificamerican.com/article/heat-and-humidity...
What might happen is portrayed pretty vividly at the start of Kim Stanley Robinson's Ministry for the Future:
https://en.wikipedia.org/wiki/The_Ministry_for_the_Future
[And yes I know this is a novel].
https://www.eea.europa.eu/data-and-maps/indicators/heat-and-...
> The PESETA study estimates that, without adaptation and physiological acclimatisation, heat-related mortality in Europe would increase by between 60 000 and 165 000 deaths per year by the 2080s compared with the present baseline, with the highest impacts in southern Europe. [...]
> Another study estimates that climate change will lead to an increase in hospital admissions owing to heat-related respiratory diseases from 11 000 admissions (0.18 %) in the period 1981–2010 to 26 000 (0.4 %) in 2021–2050. The total number of hospital admissions and the increase as a result of climate change are largest in southern Europe, with the proportion of heat-related admissions for respiratory conditions expected to approximately triple in this region over this time period [...]
On the other hand...
> The PESETA study estimated that cold-related mortality would decrease by between 60 000 and 250 000 deaths per year by the 2080s, which is about the same magnitude as the projected increase in heat-related mortality [xx]. The PESETA II study no longer considers a potential reduction in cold-related mortality in its climate impact estimates [xxi]. The choice not to include cold spells reflects recent evidence that does not suggest a significant shift in the balance of deaths between winters and summers because of lower cold-related mortality [xxii]. However, the risk from (moderate) cold is expected to continue to account for most of the temperature-related risk throughout this century [xxiii].
It's not getting cold enough, long enough, to kill the Pine Beetle or ticks. The result is huge forest fires (e.g. Ft. McMurry) caused by dead trees -- killed by said beetles -- or explosions of ticks and increases in Lyme in Eastern Canada.
if you have kids they will probably be dead
if you don't have kids but are planning on having kids within <9 years your kids will probably be dead.
If you don't have kids but are planning on having kids within 10-12 years your kids will probably not be dead (at current average life expectancy) but will probably be so old they are almost dead and their best years will have been behind them anyway. Perversely as climate change is supposed to decrease average life expectancy your kids will probably be dead anyway.
If you are planning on having kids in 12-20+ years they will probably not be dead then.
If you have kids within 1-20 years and they have kids your grandkids are going to be dealing this somewhere between their teens to their middle age, depending on how soon you have your kids and how soon they have their kids but going by current demographics, probably middle age if you have a kid now and probably teens or younger if you have one in 20 years.
on edit: I do not find the argument particularly strong unless one is not good at simple math, or one does not care about grandkids.
* Food insecurities will be the first challenge, as it will come first probably and will have impact on democracy and will transform food import-dependant countries in powderkegs. US and Europe will be spared by this (southern Spain and Italy not so much, but still). Syria and Liban will be crushed.
* Wet-bulb temperature will become the second challenge by 2080, and 2060 if nothing is done by 2040. When Florida, South carolina and south cali will be hit by this, people might start consider moving, or living underground more than half the year. Europe will be spared by this as most projection say the Gulf stream will likely still work until the north pole ice melt, so 2150-2200.
* As the troposphere warms up and the stratosphere cool down, we will witness harsh meteorological events that will strain infrastructure all around the world.
* Ectothermics species will work at an higher level, their metabolism will be boosted and we will see pests working harder (and at higher latitudes). While endothermic species will disappear quietly. Same thing with mushrooms (that will worsen the 1st issue)
* Yes, sea levels will rise. It proably wont have any impact until 2080 for island nations (unless is contaminate their fresh water reserves).
This one won't spare some big regions of USA.
well if you want people to change their behavior and some people seem focused on sea levels you might want to address their worry instead of telling them, don't worry about that. That's like a marketing thing though - there are other issues.
I for example believe it is possible to note issues regarding rising sea levels without throwing all other issues out or refusing to focus on them as well, that is to say the focus of human conversation and mind is not the same as the focus of a camera.
finally
> Food insecurities...US and Europe will be spared by this
>Wet-bulb temperature...Europe will be spared by this
>It probably wont have any impact until 2080 for island nations
I'm in Denmark, which is primarily a coastal and island nation without any notable high ground. So obviously anyone who was in my position might consider the sea-level a more personally problematic focus area than #5, even though the other events are more problematic for the world as a whole. I also think the Ectothermics species issue might not be as big a problem in Denmark.
>Following this, we therefore propose to linearize the relationship between average rate of sea level rise and temperature increase representing the entire preceding century. The slope of this relationship then expresses how sensitive sea level is to century-timescale warming, and we will refer to it as the transient sea level sensitivity (TSLS). The intercept – where the sea level rate of change is zero – we interpret as a balance temperature.
I'm not an expert on climate and am therefore not qualified to opine on the suitability of a simple linear model for this sort of system.
This is so beautiful, it can only be improved as a haiku:
One cannot opine
On such suitability
Oversimplified
Indeed, this should come as no surprise, nor make any eyebrows rise: Excessive industrial enterprise cannot but give rise to this outcome. Any hope of averting elevated sea levels has all but vaporised.