[HN Gopher] Shrinking freshwater availability increasing land co...
___________________________________________________________________
Shrinking freshwater availability increasing land contribution to
sea level rise
Author : ornel
Score : 106 points
Date : 2025-08-03 19:49 UTC (3 hours ago)
(HTM) web link (news.asu.edu)
(TXT) w3m dump (news.asu.edu)
| jfengel wrote:
| Unlike climate change, this is a self correcting problem. We'll
| tap the last of the fresh water, and then no more sea level rise
| (from that source).
|
| Problem solved, once and for all.
| treyd wrote:
| The polar ice caps are the same way. Once we melt all the ice
| then the sea level rise will stop, and we can just deal with
| the change in lifestyle.
| oh_my_goodness wrote:
| I think the change in lifestyle from using up all the
| groundwater would be pretty severe.
| micromacrofoot wrote:
| personally i'm just going to evolve
| riffraff wrote:
| Not developing mutations to live in a mad max style
| future shows lack of initiative
| DaveZale wrote:
| I have a tub in the kitchen sink to capture all
| dishwater, and make 4-5 trips outside to dump the water
| daily, into watering tubes that are six inches deep,
| around the dripline of each tree. Here in the SW US it is
| almost pointless to water at the surface, 90% or so is
| lost to evaporation within a day.
| fooker wrote:
| You can also hibernate in pokeballs when things get bad.
|
| Foolproof plan.
| Gibbon1 wrote:
| Considering current shitshow reaction to having to deal with
| smaller issues I'm not optimistic about how that's going to
| play out.
| marcosdumay wrote:
| Well, that applies to most of our habitat-change problems.
| causal wrote:
| Solutions that include mass die-off of human populations are
| generally considered incomplete
| Ekaros wrote:
| But they are effective in reducing emissions.
| firstworldfail wrote:
| I love the first world perspective. It pretends to be
| erudite while being completely inhuman. As if "emissions"
| are something you could ever get rid of. Any excuse to
| avoid making their own lives more efficient or the
| distribution of resources more fair.
| aydyn wrote:
| What is a "fair" distribution of resources in your
| perspective, in general.
|
| Edit: Um okay, downvotes are quite telling.
| ojbyrne wrote:
| I believe it was a joke.
| makeitdouble wrote:
| This is an often repeated point, and many proponent of
| population reduction embrace it.
|
| I think that's completely ignoring our consumption
| patterns. We're totally up to the challenge of burning
| twice the resources with only half the population.
| ada1981 wrote:
| It's a good reminder that "climate change" will be a minor
| inconvenience for the rich, and an existential crisis for
| everyone else.
|
| And that most of the inconvience will be needing to deploy
| robots to keep the poor away.
| slt2021 wrote:
| thats what revolutionary movements are for: to organize
| "everyone else" and physically purge the elites that dont
| care about the crisis affecting regular people
| andyferris wrote:
| Just like the coal, gas, oil and forests - so exactly like
| climate change, in fact...
|
| (It's a problem that saturates but not a problem that self-
| corrects, and the saturation point is undesirable in any case)
| giantg2 wrote:
| So they claim the majority of the water is ground water and also
| that it is due to climate change. But I thought I've seen other
| studies talking about how ground water is being depleted at a
| higher rate than it could be replaced, even using historical
| averages. This sounds more like a population/industrialization
| issue than a climate issue.
| pstuart wrote:
| I think the distinction is between rainwater runoff vs aquifer
| depletion. They are related, and if we were collectively
| smarter we would do a better job of managing the runoff to help
| restore the aquifers.
| DaveZale wrote:
| in some parts of the country (US), interstate water
| agreements promise a certain volume of water to be delivered
| from one state to another, in which cases, runoff is
| sometimes required. Legal agreements.
| cycomanic wrote:
| > So they claim the majority of the water is ground water and
| also that it is due to climate change. But I thought I've seen
| other studies talking about how ground water is being depleted
| at a higher rate than it could be replaced, even using
| historical averages. This sounds more like a
| population/industrialization issue than a climate issue.
|
| I'm not sure I understand where you see a contradiction. Land
| areas are using groundwater faster than it can be replenished,
| so land is getting drier. That's according to the article (just
| basing of the summary not the scientific one) is driven by both
| overuse and drier and warmer weather. The thing is, that's a
| feedback loop, if it gets drier we'll be using more groundwater
| for irrigation. So both processes are driven by climate change.
| garrettdreyfus wrote:
| I'm not sure this title is completely correct
|
| "The researchers identified the type of water loss on land, and
| for the first time, found that 68% came from groundwater alone --
| contributing more to sea level rise than glaciers and ice caps on
| land."
|
| They are saying the leading loss of water loss is from ground
| water. The largest contributor to sea level rise I would guess is
| still thermosteric sea level rise due to the ocean becoming
| warmer and less dense
|
| See ipcc https://www.ipcc.ch/report/ar6/wg1/chapter/chapter-9/
|
| 9.6.1 Global and Regional Sea Level Change in the Instrumental
| Era
|
| In particular, Cross-Chapter 9.1, Figure 1 | Global Energy
| Inventory and Sea Level Budget. Panel b
|
| EDIT: @dang could the submission title be changed to the article
| or journal article title?
|
| "New global study shows freshwater is disappearing at alarming
| rates"
|
| Or
|
| "Unprecedented continental drying, shrinking freshwater
| availability, and increasing land contributions to sea level
| rise"
| garrettdreyfus wrote:
| My reading of Figure 6
| https://www.science.org/doi/10.1126/sciadv.adx0298 suggests
| that this study still has thermosteric effects making up the
| majority of sea level rise.
|
| I also highly recommend reading up on the GRACE satellite used
| in this study it is amazing
| https://gracefo.jpl.nasa.gov/resources/50/how-grace-fo-measu...
| yboris wrote:
| Thank you for sharing, GRACE-FO feels to me like a brilliant
| design!
| srameshc wrote:
| > New findings from studying over two decades of satellite
| observations reveal that the Earth's continents have
| experienced unprecedented freshwater loss since 2002, driven by
| climate change, unsustainable groundwater use and extreme
| droughts.
|
| The title captures the crux of the story
| garrettdreyfus wrote:
| Sorry I am referring to HN submission title not the article
| title
| ornel wrote:
| Quote from the paper: "the continents are now the leading
| contributor (44%) to mass-driven GMSL rise". As regards to non-
| mass-driven rise, another article[0] states, "Ice-mass loss--
| predominantly from glaciers--has caused twice as much sea-level
| rise since 1900 as has thermal expansion". I think the findings
| about sea level rise are as interesting as the ones about fresh
| water disappearance.
|
| [0] https://www.nature.com/articles/s41586-020-2591-3
| garrettdreyfus wrote:
| The study you cite is talking about sea level rise since 1900
| which is a very different story.
|
| The IPCC section "9.6.1.1 Global Mean Sea Level Change Budget
| in the Pre-satellite Era" says Since SROCC, a new ocean heat
| content reconstruction (Section 2.3.3.1; Zanna et al., 2019)
| has allowed global thermosteric sea level change to be
| estimated over the 20th century. As a result, the sea level
| budget for the 20th century can now be assessed for the first
| time. For the periods 1901-1990 and 1901-2018, the assessed
| very likely range for the sum of components is found to be
| consistent with the assessed very likely range of observed
| GMSL change (medium confidence), in agreement with Frederikse
| et al. (2020b; Table 9.5). This represents a major step
| forward in the understanding of observed GMSL change over the
| 20th century, which is dominated by glacier (52%) and
| Greenland Ice Sheet mass loss (29%) and the effect of ocean
| thermal expansion (32%), with a negative contribution from
| the LWS change (-14%). While the combined mass loss for
| Greenland and glaciers is consistent with SROCC, updates in
| the underlying datasets lead to differences in partitioning
| of the mass loss."
|
| Edit: by a different story I mean a different story from what
| _is_ the leading driver of sea level rise. Sea level rise
| from ice melt was larger since 1900 because sea level rise in
| general was less fast back then and global mean temperature
| rise was much smaller so thermosteric sea level rise played
| less of a role. Thermosteric sea level rise is larger than
| ground water factors, both will be eclipsed by ice melt in
| the upcoming century.
|
| I would note the authors pointedly do not call it the leading
| driver of sea level rise.
| garrettdreyfus wrote:
| See table 9.5
|
| https://www.ipcc.ch/report/ar6/wg1/chapter/chapter-9/
| garrettdreyfus wrote:
| Although to your point it does vary alot over different
| windows of time.
| perching_aix wrote:
| So let me get this straight:
|
| - sea level is formally referred to as Global Mean Sea
| Level (GMSL)
|
| - its change is segmented into two subcategories in
| literature(?), mass-driven (e.g. ice melting?, freshwater
| runoff?, freshwater water cycle stuff?) and non-mass-driven
| (e.g. thermal expansion?)
|
| - freshwater loss from land was found to be at present the
| lead driver of the mass-driven change as per the paper
| (over what timeframe?)
|
| - title says it's the primary driver for GMSL change
| overall, which this alone doesn't support (i.e. the title
| is a lie)
|
| - @ornel (the person posting) points to another study that
| claims mass-driven change is the leading change, hence the
| title [0, this doesn't pass my smell test but i see the
| logic]
|
| - you point out that that's glossing over that that other
| study is counting from 1900, but if one shrunk the
| evaluation window, the non-mass-driven causes would be the
| drivers now [1, this doesn't pass my smell test either, but
| i see the logic here as well]
|
| The latter point then begs the question though, what is the
| time window in this case then, and how stable that result
| is? What would be an "appropriate" time window to choose,
| and how would one derive that?
|
| Regarding my non-passing smell tests, imagine the following
| scenario for some event:
|
| - category A: 51% of the total
|
| - cause A1: 26% of the total
|
| - cause A2: 25% of the total
|
| - category B: 49% of the total
|
| - cause B1: 27% of the total
|
| - cause B2: 22% of the total
|
| In this case, category A will be the lead contributor, but
| individually none of its contributing causes will be,
| addressing [0]. The causes will be ordered like so instead:
| B1 > A1 > A2 > B2. More elaborate variations are possible
| of course. For [1], you can imagine the same scenario just
| in reverse.
|
| Did I get all this right?
| garrettdreyfus wrote:
| Hi,
|
| I appreciate the effort in your comment. I think upon
| further reflection my simpler objection is calling
| freshwater loss the main driver of sea level rise when
| the journal article and news article don't. Also I would
| note this is only one study.
| perching_aix wrote:
| > I appreciate the effort in your comment.
|
| Thanks for that! I do wish it wasn't necessary though,
| but I guess that's just how real life problems go.
|
| > I think upon further reflection my simpler objection is
| (...)
|
| Right, that's perfectly fine; just got curious and you
| seemed informed.
|
| Editorializing the titles in general is against the
| guidelines here anyhow to be fair, I'm expecting it will
| be updated by the mods eventually:
| https://news.ycombinator.com/newsguidelines.html
| garrettdreyfus wrote:
| I very much like your categories point here by the way!
| cwillu wrote:
| @dang doesn't do anything; but they're quite responsive to
| email.
| dang wrote:
| Ok, I've put the second suggestion up there. Thanks!
|
| (Submitted title was "Freshwater loss from land is the lead
| driver of sea-level rise")
| robertclaus wrote:
| Interesting second order effect of global warming.
| cubefox wrote:
| Original title: "New global study shows freshwater is
| disappearing at alarming rates"
| SoftTalker wrote:
| So go long on desalination tech?
___________________________________________________________________
(page generated 2025-08-03 23:00 UTC)