The 100th Meridian, Where the Great Plains Begin, May Be Shifting | Hacker News Reader

The 100th Meridian, Where the Great Plains Begin, May Be Shifting

ldeo.columbia.edu

97 pointsclumsysmurf32 comments

I live on this line (Oklahoma). We go through feast or famine with water here and have for 100s of years.

Here's a nice graph from OWRB (old 2011 data but still shows the swings): https://i.imgur.com/vLA1hAk.png

Source: (slow loading) http://www.owrb.ok.gov/supply/drought/pdf_dro/DroughtFactShe...

It's on page 2.

If rainfall is normally distributed, then this outcome is expected anywhere. Are you trying to say that the average (34") is near the threshold for feast/famine?

Feast or famine was a turn of phrase, meant to illustrate that we're either flooding or in a drought along this 100th Meridian.

The minimum seems to be ~19 inches which is quite a bit of rain. Around 1/2 the US averages less than that: http://www.eldoradocountyweather.com/climate/US%20Climate%20...

This is the state average.

Typically the western part of the state (west of the 100th Meridian) is dry as a bone and in constant drought, while the eastern side is flush with water. Along the 100th we get both extremes.

This summarizes it pretty much perfectly: http://droughtmonitor.unl.edu/CurrentMap/StateDroughtMonitor...

I'm not well versed in that kind of thing, but doesn't "drought" just mean with respect to the average? In other words, what counts for a drought in western Oregon is different from a drought in southern Arizona, right?

Yes, drought is for a region based on its averages. One problem is droughts and wet spells can happen on periods with length of a decade.

During the flood of ‘93 things got so bad there were college professors making allowances for people who wanted (or needed) to leave school and go bag sand along the Mississippi. Edit: this despite the peak of the flood happening weeks before fall semesters were due to start.

Wonder when the next one will be.

From the article, it looks like precipitation has varied normally, but temperature has been increasing:

> Now, the researchers say, warming climate appears to be pushing the divide east. In the northern plains, rainfall has not changed much, but temperatures are going up, increasing evaporation from the soil. Further south, concurrent shifts in wind patterns are in fact causing less rain to fall. Either way, this tends to push western aridity eastward. Data collected since about 1980 suggests that the statistical divide between humid and arid has now shifted closer to the 98th meridian, some 140 miles east.

You can see the statewide temperature increase over time here: http://climate.ok.gov/index.php/climate/climate_trends/tempe...

You may also be interested in the Ogallala aquifer (https://en.wikipedia.org/wiki/Ogallala_Aquifer), which is kind of important to agriculture west of the 100th (https://www.scientificamerican.com/article/the-ogallala-aqui...).

If you're interested in some newer data for the High Plains Aquifer (AKA Ogallala Aquifer), try this:

https://www.usgs.gov/news/usgs-high-plains-aquifer-groundwat...

Tipping my hat to the Tragically Hip reference. RIP Gordy.

"New Orleans is sinking man and I don't wanna swim".

If you'd like to read more about this, I recommend John Wesley Powell's biography: "Beyond the Hundredth Meridian: John Wesley Powell and the Second Opening of the West" https://amzn.to/2H2v7oZ

Another good one (though a bit dated now) is Great Plains by Ian Frazier.

https://www.amazon.com/Great-Plains-Ian-Frazier/dp/031227850...

Maybe it's just me, but that headline sounds as if the 100th Meridian, rather than where the Great Plains begin, is shifting.

Perhaps a better headline would be "The Great Plains, which began at the 100 Meridian, may be shifting".

It’s a play on a song lyric

https://g.co/kgs/AgyHpo

Ah, I see. Unfortunately, I'm not familiar with that part of (edit: North) American culture.

More of a Canadian culture reference, or at least more widely recognized in Canada.

What is it about the climate change weather patterns that's pushing the line East? It's not like the Rockies have gotten taller. That is, a storm moving east is depleted when it hits the Rockies. That leaves a desert to the East. Are there less storms? Faster moving storms? Both?

"In the northern plains, rainfall has not changed much, but temperatures are going up, increasing evaporation from the soil. Further south, concurrent shifts in wind patterns are in fact causing less rain to fall. Either way, this tends to push western aridity eastward." - the linked article

Thx. Sorry. I missed that.

The 100th Meridian coincides almost exactly with the western edge of the Gulf of Mexico. If I understand correctly, moisture comes up from the south, not just from the Rockies. If the wind pattern changes so that more air comes from the west and less from the south, that moisture flow is reduced.

Actually, a lot of storms start along the front range of the Rockies and then roll east from there.

Fascinating! It's very interesting to see some real life effects of climate change in the lower 48.

I would love to see some future projections here.

There are many more examples:

https://www.epa.gov/climate-indicators/downloads-indicators-...

Thanks for that link! Never seen that before.

I want to emphasize the YouTube video at the bottom of the article: https://www.youtube.com/watch?v=BCFo0a8V-Ag

As soon as I saw the headline, I knew I couldn't let a reference to my favourite band go unmentioned. It is almost criminal how underappreciated the Tragically Hip are as a band.

It is almost criminal how underappreciated the Tragically Hip are as a band.

This statement is somehow perfect.

I came to say the same thing. RIP Gord Downie

  Driving down a corduroy road,
  Weeds standing shoulder high
  Ferris wheel is rusting off in the distance
  At the hundredth meridian 
  At the hundredth meridian
  At the hundredth meridian
  Where the great plains begin

Hello fellow Canadian

Reply on news.ycombinator.com