We still don’t have the fine grained modeling to have predicted this so that we need caution in after the fact assertions, but this does have the smell of an attributable event.

BTW, theres an attribution study that links the deadly European heat wave to warming so some scientists are willing to link some individual events. One just needs to be pretty careful.

[JR: Try again.]

OK, could you explain why, if the mountains of Colorado and Wyoming have twice as much snow at this time than they do normally, the Colorado River won’t deliver more water to the reservoirs of the southwest?

[JR: Early snowmelt kills off the rivers before they are most needed.]

JR: note that there is a *lot* of confusion about the term “ice age”.
I know you know all this, but to remind everyone to think about what “entering an ice-age” means:

Looking at ice age volume, we have, looking at the *last* ice age:

A: the (usual) point of highest temperature, after which the temperature slowly lowers, with jiggles, say ~120K years ago.

B: (slightly later, normally) the point of *Lowest* ice volume, after which the ice slowly expands, with jiggles.

C: at some point, Toronto’s location (to pick an intermediate example) was covered with ice

D: Finally, temperatures reached their lowest point, and ice its maximum extent. Then Milankovitch takes over… temperatures rise, CO2+water vapor amplification cut in, then ice-albedo feedback, and temperature rises quickly, and ice disappears

Now, I don’t think anyone would consider point A the beginning of the ice age this time, as the Holocene entirely follows that. Ruddiman thinks (in Plows, Plagues & Petroleum) that there were signs of an incipient rebuild of ice cover in Baffin Island, but of course, the glaciers are not advancing now.

Anyone would agree that C & D are parts of a real Ice Age, but the widely-used phrase “heading back to an ice age” seems meaningless, since it often takes 10s of thousands of years, even naturally.

Of course, as seen in 5Myear chart, in the last ~3Myears, the Earth has been in a hair-trigger state that allows these big swings, which only happens with the right continental configurations and CO2/CH4 levels. Since Milankovitch cycles aren’t going to change, and continents don’t move that fast, we certainly could return to the right side of that graph where there is little ice on the planet.

Of course, if we ever really faced an icea age, and still had a tech civilization, we could probably fix that with some long-lived, intense GHG like SF6…

[JR: The climate changes when it is forced to change. Historically that has been driven by either large emissions of greenhouse (or other) gases or changes in the Earth's orbit, which provide a small initial warming that triggers amplifying feedbacks and the carbon cycle. Many scientists believe that absent human action, we would over the course of the next few thousand years slowly enter in another ice age. The greenhouse gases we are emitting at a rate 200 times faster than has ever occurred during the natural, amplifying cycles, have overwhelmed the slow cooling we might otherwise be experiencing and driven us into a rapid warming cycle.]

If one looks at the Colorado River, the major water source for the southwest, it’s basin extends up into northern Colorado and Wyoming. Snow totals are readily available for the ski resorts. Vail, for example, has had 371″ of snow this winter while a normal year is only 184″ Having twice as much snow pack means a lot more water for the southwest this year.

[JR: Try again.]

The excess carbon added by humans to the active carbon cycle since the start of the industrial revolution has completely upset all of that; GW = AGW.

I.e., even if no snow is involved, there can be a big difference between:
a) A huge rainstorm, which causes a lot of runoff.
b) The same total inches of rain, spread over many weeks.

Snow+slow melt ~ b), but snow + fast melt is more like b).

Of course, this is a particular issue for you & I in CA, but further North, they worry about it in Washington. But at least, they tend to get some rain up there in the summer, unlike down here. Given the amount of agriculture on the West Coast, this is serious.

Wouldn’t be surprised. Here in Chicago they’ve been keeping weather records for 140 years and this winter ranked in the top 10 for both snow and cold.

If as you say the ground is largely frozen and there is a build up of ice downsteam which is preventing free flow of water we should conclude the unusually cold and snowy winter must be something to do with this event.

Neil – I did some searching but found nothing definitive.

The best I found is that the ground is very saturated due to a lot of precipitation this year. And it’s largely frozen, which means that it won’t accept more. Finally there have been some very large snowfalls recently.

Let me add a guess that the Mid West might be experiencing some large temperature swings. That’s certainly happening where I live on the west coast. Big snows followed by some “unseasonable” warm weather would release a lot more water than would gradual spring warming.

Perhaps someone else has more facts….