
Receding glacier causes Canadian river to vanish in four days - Red_Tarsius
https://www.theguardian.com/science/2017/apr/17/receding-glacier-causes-immense-canadian-river-to-vanish-in-four-days-climate-change
======
OliverJones
There's another possibility of the event this author calls "river piracy." The
Mississippi river is chronically at risk of being grabbed by the Atchafalaya
River.

John McPhee wrote about this in 1987.
[http://www.newyorker.com/magazine/1987/02/23/atchafalaya](http://www.newyorker.com/magazine/1987/02/23/atchafalaya)

~~~
nostrademons
The Salton Sea is also an example. Its current incarnation was formed through
accidental diversion of the Colorado River through an irrigation canal, and
its continued existence is sustained through agricultural runoff from diverted
Colorado River water. The Colorado River no longer reaches the Gulf of Baja in
most years.

[http://www.water.ca.gov/saltonsea/documents/history.cfm](http://www.water.ca.gov/saltonsea/documents/history.cfm)

~~~
dragonwriter
> The Colorado River no longer reaches the Gulf of Baja in most years.

As your source gets correct, the body of water in question is the Gulf of
_California_ , not the "Gulf of Baja".

~~~
narrowrail
O/T: The Baja peninsula is great for camping except June-Aug, and I've spent
~15 weeks along [what we called] the Sea of Cortez. So, I went to wikipedia
and apparently, it's gotten somewhat political. I can see both sides, but for
other folks who like to lurk talk pages (the first thread is a discussion
about what to call this body of water):

[https://en.wikipedia.org/wiki/Talk:Gulf_of_California](https://en.wikipedia.org/wiki/Talk:Gulf_of_California)

------
Almaviva
"The calculations put chance of the piracy having occured due to natural
variability at 0.5%. “So it’s 99.5% that it occurred due to warming over the
industrial era,” said Best."

We need to train children in school to understand what statistical confidence
means, so that we stop saying wrong things like this.

~~~
acover
Why is it wrong?

If you reject the null hypothesis with a 99.5% chance it is not a type 1
error.

~~~
Para2016
You can't say it's 99.5% due to global warming alone though. You can say 0.5%
occurring by random chance but you can't just ascribe everything to one causal
factor. Could be multi-factorial.

~~~
interurban
While the exact language in the quote is perhaps implying something, it only
directly says the that the cause is warming during the industrial era. It
doesn't provide any direct information about causal factors.

~~~
Para2016
In the article: "So it’s 99.5% that it occurred due to warming over the
industrial era," said Best.

I don't have a problem with them saying for example - "We believe that the
river changed due to warming over the industrial era"

I don't really have a problem with anything they conclude to be honest, I was
just answering another guy's question. Shitty of HN users to give me negative
points over it. I feel like I'm on Reddit again.

------
douche
This kind of thing has happened several times in China in recorded history
with the Yellow River, to the point where sometimes the river has flowed into
the ocean north of the Shandong peninsula and sometimes south of it.

[https://en.wikipedia.org/wiki/Yellow_River#History](https://en.wikipedia.org/wiki/Yellow_River#History)

~~~
jonknee
Rivers re-route themselves frequently, the difference is cause (sediment for
the Yellow River, melting glacier for the Slims).

------
niftich
I was just looking at the Alsek valley on Google Earth the other day. It's
(obviously) a water-level route from behind the mountains to the coast, and
abuts the drainage divide with the Yukon.

The entire Alsek-Tatshenshini-Kaskawulsh-Dezadeash system's upper reaches
occur in glacier-scoured valleys so ice damming or stream undercutting could
greatly change the direction rivers flow. The northwest-southeast trench that
includes Kluane Lake and continues beyond Haines Junction is the Shakwak
Trench [4], created by the Denali fault.

Here's a map of the article's glacier and the surrounding area:
[http://i.imgur.com/tL84Bd0.jpg](http://i.imgur.com/tL84Bd0.jpg) (edited from
the park map [1])

A different scan from a 1985 topo map:
[http://i.imgur.com/cVmWLlP.jpg](http://i.imgur.com/cVmWLlP.jpg) (cropped from
[2])

Meanwhile, 90 kilometers downriver (south) along the Kaskawulsh->Alsek, the
west-to-east Lowell Glacier used to squish the north-to-south Alsek River
against the far valley wall, damming it and causing a lake to extend upstream
[3]-- the last time this happened was around 1850; the source estimates it'd
take a year of being dammed for lake to extend up the Dezadeash to Haines
Junction.

[1] [http://www.pc.gc.ca/en/pn-
np/yt/kluane/visit/~/media/088B38E...](http://www.pc.gc.ca/en/pn-
np/yt/kluane/visit/~/media/088B38E3A3D14CECA4035A16E0CEB0B7.ashx) [2]
[http://www.canmaps.com/topo/nts250/med/115b.htm](http://www.canmaps.com/topo/nts250/med/115b.htm)
[3]
[http://www.geology.gov.yk.ca/lowell_glacier.html](http://www.geology.gov.yk.ca/lowell_glacier.html)
[4]
[https://en.wikipedia.org/wiki/Geography_of_Yukon#Physical_ge...](https://en.wikipedia.org/wiki/Geography_of_Yukon#Physical_geography)

------
Mz
One problem with the way this is framed:

Rivers have historically _meandered._ They didn't have a set path. The modern
expectation that rivers have a set path is one we tend to try to actively
enforce.

Elsewhere in comments here, someone noted that the Salton Sea is similar. But
if you read _Salt Dreams,_ Native Americans had oral history suggesting that
there had been a lake there previously. Geological records agree with the oral
history.

------
titojankowski
Sweet, so what should we build to change this? Giant carbon-sucking machines,
cube-sats pointed at glaciers? (planet labs is doing cool stuff in this space,
including a project to count every tree on Earth every day). Solutions
welcome!

~~~
spodek
At a low level:

\- Have fewer children

\- Burn fewer fossil fuels (less driving, flying, heating, cooling, more
wearing sweaters at home in winter, etc)

\- Eat less meat

\- Develop technologies to create energy without fossil fuels

At a higher level

\- Stop associating consumption and material accumulation with happiness

\- Stop targeting growth (population, GDP, etc) as solution to so many
problems

\- Take personal responsibility for what you do. Stop saying if others don't
change my change won't make a difference. You are responsible for what you do
even if others don't change.

At the top level:

\- Change you beliefs and goals so that instead of asking others, you find
what you can do and do it. There is overwhelming amounts of information for
what you can do already on the web. If you want to act, act.

~~~
crazy2be
I'm not convinced having fewer children will help anything and I wish people
would stop repeating this. _People_ emit very few greenhouse gasses as a
virtue of their existence, the extreme majority of them are emitted by
lifestyle choices.

Even in developed countries the differences are stark. Qatar emits 54.7 tons
of CO2 equivalent per capita, the United States 24.3 tons, Germany 12.3 tons,
Switzerland 7.2 tons. A difference of almost 10x, with countries that all have
similar standards of living! In a relatively undeveloped country like Burundi,
the emissions are a mere 0.4 tons per capita[0]. A difference of literally
100x!

The best fix is a revenue-neutral carbon tax, with import tariffs on goods
from countries that do not have such taxes (i.e. China). This internalizes the
externalized costs of CO2 emissions, automatically encouraging development of
more energy-efficient everything.

[0] Data from 2000, unfortunately, but the numbers have not changed in
magnitude since then.
[https://en.wikipedia.org/wiki/List_of_countries_by_greenhous...](https://en.wikipedia.org/wiki/List_of_countries_by_greenhouse_gas_emissions_per_capita)

~~~
titojankowski
Have either of you checked out Bret Victor's "What can a technologist do about
climate change?"

[http://worrydream.com/ClimateChange/](http://worrydream.com/ClimateChange/)

Would be cool to hear how it resonates (or not) with your perspectives.

------
inetknght
I'm thinking you're commenting on the wrong article ;)

Did you mean ->
[https://news.ycombinator.com/item?id=14131759](https://news.ycombinator.com/item?id=14131759)

~~~
kensai
Guys, I seriously do not know wtf happened. I never opened this "Receding
glacier" thread. I was commenting on the Intel thread and my comment somehow
ended up here. I got aware of it because of all these negative points which
came quite unexpected.

Could it have been a glitch in the database?

~~~
sctb
I'm not sure what might've happened, but the web request logs show that
comment being submitted to this thread. We've restored your karma and moved
your comment to the right thread.

------
LeifCarrotson
I think you meant to put this comment in this thread:
[https://news.ycombinator.com/item?id=14131759](https://news.ycombinator.com/item?id=14131759)

~~~
sctb
We detached this comment from
[https://news.ycombinator.com/item?id=14132125](https://news.ycombinator.com/item?id=14132125)
and marked it off-topic.

------
necessity
Booo it's the ghost of global warming! Always threatening, never happening.

~~~
komali2
Why do you believe this?

~~~
komali2
Shame, it was flagged and removed. It was a comment that was highly sarcastic
and critical of climate change, but I'd say no more sarcastic than any other
comment we might find on here. Perhaps we could have benefited from learning
why people continue to falsely believe climate change isn't real.

~~~
DanBC
"Booo it's the ghost of global warming! Always threatening, never happening."
is a worthless pointless comment and there's not going to be any useful
discussion coming from it.

It's exactly the kind of comment that needs to be downvoted and flagged.

Also, flagging doesn't really remove anything. You can change the "showdead"
setting in your options to see all flagged comments.

~~~
komali2
Oh, I didn't know that, thank you.

------
sandworm101
Lol "immense" river 150m wide. Ok guardian readers, that may be an immense and
scary river in the UK but canadians reserve words like immense for far larger
things. At 15km this river may well be the largest thing ever seen by a brit,
but canada has something like 50 rivers over 350 miles long. This is a glacial
stream by the standards of The North, a part of canada bigger than all western
europe. My local dog beach has a river 150m wide.

~~~
mattmanser
One writer describes 15km as immense and suddenly all Guardian readers are
idiots?

For reference, the Thames is 350km long.

~~~
sandworm101
Idiots no, but given how UK publications so often describe geographical
features one is left with the impression that the UK is sized like legoland.
This is not a large river and, given the climate change aspect to the story,
to desribe it as such is dishonest.

~~~
komali2
Hrm, I'd hate to say it like this but it's not always the length that matters.
Did you read the bit about the volume of water that the pirating river
increased by?

