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How many feet above current sea level will I have to reside to be safe in 10 years, 20 years?
How many feet above current sea level will I have to reside to be safe in 10 years, 20 years?
I don't understand this part: "In total, Antarctica has shed some 2.7 trillion tonnes of ice since 1992, corresponding to an increase in global sea level of more than 7.5mm." If the melting ice of Antarctica contributes only 0.3mm per year to the annual 6mm rise of sea levels, what exactly is causing a 20x larger change? [added] On the other hand a NASA study published in 2015 [1] indicated that Antarctica has been s…
Water expands when it gets warmer.
Something is not right. Either ice melting has been contributing 4mm/year to recent decades of sea rise, or the contribution is slightly negative (in the largest ice sheet, over Antarctica). Thermal expansion of ocean water on its own does not adequately explain it.
[1] Contributions to Global Sea-Level Rise https://www.nap.edu/read/13389/chapter/5
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One could dogmatically down-vote, or one could provide references to scientific discussions that cover the contradictory stories... You know who you are.
I expect to see #FloridaMan stories about sea level rise before we do something constructive like greatly increase the gas tax.
and to stop subsidizing meat and dairy production and associated crops (corn, soy).
Earlier quoted context omitted.
50cm by 2100. That's just under 20 inches for Imperialists. This assumes a linear rise of 6mm/year. So in the next 10 years sea level would rise by 6 cm (just over two inches; I understand there are twelve of those in a foot, so we're not talking "feet" until 102 years from now).
That's also average sea level. If hurricanes get more powerful or more frequent, then you're going to want to account for the storm surge as well.
[1] https://www.wsj.com/articles/the-hurricane-lull-couldnt-last...
How many feet above current sea level will I have to reside to be safe in 10 years, 20 years?
For friends looking to buy coastal property on ~30 year loans I advise that they need to be able to sell those properties some decades out from a more general concern / awareness of the risk.
Earlier quoted context omitted.
That's also average sea level. If hurricanes get more powerful or more frequent, then you're going to want to account for the storm surge as well.
The historical record shows that hurricanes have gotten neither more frequent nor more powerful. [1] [1] https://www.wsj.com/articles/the-hurricane-lull-couldnt-last...
"More thoughtful and effective disaster policies are needed because the future will bring many more weather disasters like Hurricane Harvey, with larger impacts than those of the recent past." (From your own link)
Assuming these estimated 2,700 Gt (the rounded 3 trillion) have not been steadily replaced by new water on top of the ice sheet [1] the reported loss amounts to a mere 0.01% of the total ice sheet.
I don't see cause for panic.
[1] https://www.nasa.gov/feature/goddard/nasa-study-mass-gains-o...
I don't understand this part: "In total, Antarctica has shed some 2.7 trillion tonnes of ice since 1992, corresponding to an increase in global sea level of more than 7.5mm." If the melting ice of Antarctica contributes only 0.3mm per year to the annual 6mm rise of sea levels, what exactly is causing a 20x larger change? [added] On the other hand a NASA study published in 2015 [1] indicated that Antarctica has been s…
Antarctica's contribution to sea level rise per year is fairly small. The largest portion comes from loss of land-ice like mountain glaciers and snow pack. Mass loss from the Greenland Ice Sheet is also substantial, contributing about 2.7 mm/yr to sea level change. Groundwater withdrawal is a measurable component of modern sea level rise. Aside from these mass-transfer mechanisms, there is also ocean warming (water generally expands as it get warmer) and salinity changes that don't affect the amount of water in the oceans, but do affect its volume. Loss of sea ice (which floats on top of water and is not supported from below by solid earth) does not contribute to sea level change, as the sea ice is already displacing an amount of water equal to the amount of ice doing the displacing.
That 2015 Jay Zwally paper should not be taken as truth, as there are substantial reasons to doubt the impact of the findings. In that paper Zwally uses a set of satellite laser altimeters operating over different epochs and neglects to co-register the different platforms in an intelligent way. There was actually major hubbub around that paper and most glaciologists recognize the claim that "Antarctica is gaining mass" is probably incorrect.[0] Zwally has a pretty big ego and was happy to get the publicity anyways.
[0] https://www.scientificamerican.com/article/what-to-believe-i...
Rather than focusing on the big sounding absolute number in the headline, the more important number is the 3-fold increase since 2012. This means that the losses are accelerating, which is very concerning.