I did some math:
http://www.winterscience.com/lab/climate.htm
It was much bleaker than I expected. Any thoughts on the methodology or outcome?
Printable View
I did some math:
http://www.winterscience.com/lab/climate.htm
It was much bleaker than I expected. Any thoughts on the methodology or outcome?
Not in a position to offer thoughtful critique, but interested in the discussion...thx for the work
Well that was horribly depressing
Sent from my iPhone using TGR Forums
It has been a while since I have skied the northwest, however aren’t the base areas of many of the mountains already regularly at or below the rain level ?
Nice work. Seems a regionally downscaled temperature projection may prove more informative than a global projection. Maybe a shiny app for result presentation?
in before the first "it was cold today lol there's no global warming" post :rolleyes2
Yeah. Especially early in the season or in the spring.Quote:
Originally Posted by WTF is dat
Sent from my iPhone using TGR Forums
Pretty cool report. I don't think there's any denying that your numbers catch a highly probable outcome. Here in VT, I've heard predictions (from University, take it fwiw), that we'll lose half of our resorts by 2050. Without overthinking this, and I'm hardly a trained statistician or climatologist, I've always wondered how effective it is to use the century average temp? Statistically, it's probably pretty sound, but...
I guess you did the right math but you posted 25mm of rain equal 25mm of snow (you really do inches in science? ;)). The normal factor is 1:10 I thought. I guess you just had a typo.
So 25mm precipitation is 25cm of snow.
Not a climate change denier and I agree the future of skiing is looking bleak but you made the chart with the 2.6F change across the board. I may be wrong but if the average increase in global temps is 2.6f it seems like the summers are a lot hotter(more than a 2.6 degree change) and the winters are warmer(maybe not 2.6 degrees warmer). I'm not a statistician so maybe I'm totally off base here.
I think that is a good question to ask and understand. I have a feeling that it is very regionally dependent and also depends on how the local jet stream and weather patterns are affected. some areas could recieve wetter summers (cool) and warmer winters. Others might recieve cooler, wetter winters and dry hot summers.Quote:
Originally Posted by MagnificentUnicorn
The average yearly temp will go up, but how that affects the general weather patterns might affect the seasonal temps and precips is a really good mechanism to try and understand. Unfortunately, i have absolutely no idea.
It's not so much the 2 degree average rise. It's more the high end days that increase the average. Been some good days, but a lot more days where the freezing levels get crazy high. Even if the resorts where higher.. rain has been going up to the alpine a bunch this year...
I'm about to hit the half century mark, so I'm not sure how much of this demise I'll live through. I don't have kids, so not much vested in the future.. but I'm not part of the problem either. ;)
When you're talking pineapple events like this, it's not a 1-2 deg temp change that matters. These just are what they are. Warm air from the tropics, not really because of climate change and I think have always been a part of PNW winters?Quote:
Originally Posted by Ale_capone
Seems to me most of storms, snow levels depend more on whether it's SW, W, or NW flow as the existing temperature is usually quickly overrun by the incoming fronts.
I've only been here 3 winters, but is it also possible that we remember the good days and the good storms and over time forget about the rain in past years?
It's hard to abstract weather from climate. It's not uncommon to have 20 degree changes day to day, but overall I just took every hourly temperature and added the anomaly. Assumption is that although weather patterns will be different, when we sum up a longer time period it should reflect the overall pattern. We've had seasons in the past 15 years with better snowfall totals than what I would expect the 20th century average to be, but it looks like on average it's an uphill battle.
I looked at temperature ananmoloy by month (does summer bear the brunt of warming) and did not find this to be the case. It looks like all months lift similarly.
Attachment 221911
It's also not a flat lift regionally, but when you look at historical maps it's been pretty uniform thus far. I tried to pull maps off of NOAA but got this in response: "https://government-shutdown.noaa.gov"
I don't see this error, but agree it's a little odd to not use mm and C. I thought it would be easier to understand with F and inches.Quote:
Originally Posted by subtle plague
I see a problem with this statement:
Not necessarily true. It can still snow when the temp is above freezing. From all your data is there a way to find out how much snow accumulation occurred when the temp was above freezing? I have a feeling this could change the data substantially.Quote:
If it's 25°F out, and there is .1 inch of precipitation (water) measured, there will be about 1 inch of snow. If it's 35°F out, it's raining.
Sorry my mistake i didn't see the dot in the original layout :)Quote:
Originally Posted by cmor
Im getting old. just put a 0 before the .1 for old folks like me. ;)
"We can estimate the snowfall at each station by doing some simple math on the temperature and precipitation. If it's 25°F out, and there is .1 inch of precipitation (water) measured, there will be about 1 inch of snow. "
edit: AD: Yes and no. It depends hugely on air humidity. I've heard of snowfall at +3°C and more, but usually in very dry inner alpine conditions and it doesn't really accumulate in these conditions.
Not to mention at Snoqualmie Pass you can have pouring rain at 22 degrees :eek:
cmor has the data for the temps and the snow depths, so he should be able to determine whether or not this is true. I would think in this area where we're talking about snow levels often flirting with rain or snow at pass levels it could be statistically relevant.Quote:
Originally Posted by subtle plague
Your're right that it doesn't all turn to shit exactly at 32F. The two other main variables at play are RH and the vertical column of air the snow is falling through. The general rule of thumb is that the freezing level is 1000 feet above the snow level. NWAC's forecast will account for this, when there is no precip they forecast freezing level. When there is snow they forecast snow level, as they are two different things. I find that it's usually around 33F when the transition occurs,Quote:
Originally Posted by The AD
I intentionally was vague in the description you noted, and used 35 in the example because it's almost always rain by then. I used a linear scheme that changes the density of the snowfall based on the temperature. Temperature is the biggest influence here. It's an estimate because although I do have model data that I could merge to, I don't think in the end it would help all that much and it would be a lot of work. The RH is so often near 100% that it's virtually a constant. I tuned the parameters using the empirical evidence at hand, I have manual measurements I can match to snowfall at Crystal, and can see if my season totals are close for most areas. They are in the ballpark, and further mitigating the error is I'm providing a relative change. So as all models are, it is wrong, but I think it's a good estimate. I did note at the bottom I would be interested in working with anyone who has some work on this, because there is some room for improvement.
Interesting read, definitely concerning. That being said, as someone else suggested, a lot will depend on regional flows and zonal patterns , so hard to extrapolate.
Also, keep in mind, back in the early 80’s we had several years in a row where Whistler didn’t get a lot of snow, temperatures were warm and you had to download from mid-station for almost the entire season. Banff also had a major drought in the early 80’s. Much much warmer than what we have experienced here and there in the last 15 years. And theoretically we are on average warmer today than back then.
Hey cmor,
You see Dr. Ben Hatchett's (213 on TGR) recent paper on snow droughts in the Sierra? Got a bunch of regional press here locally. Check it out...
http://journals.ametsoc.org/doi/abs/...EI-D-17-0027.1
https://www.reviewjournal.com/news/s...-in-wet-years/
http://www.sfgate.com/news/article/r...A-12392508.php
https://ww2.kqed.org/science/2017/11...phill-rapidly/
Note: This tracks anecdotal evidence from friends I've chatted with who were born and raised in the Sierra Foothills dating back to the 50s. And, hell, even myself and I'm only 34.
I've been up to Mt Hood for 39 consecutive winters, snow level has gone up about 1700' in that time.Quote:
Originally Posted by ridinshockgun
Yeah, anecdotes are not data but I have a very clear memory of a couple of inches of rutted ice on Highway 26 all the way down to Zig Zag that was there for weeks (months?) during one winter in about 1994 or so. I haven't seen consistent cold temps like that in the last 10 years.Quote:
Originally Posted by k2skier112
receding /disappearing glaciers don't lie...
and they're not gonna grow in my lifetime
Yah, direction certainly plays a more dramatic role if it's a more SW, W, or NW... but a couple degrees warmer on average will make those SW flows more devastating. Ocean temp seems to be the largest determining factor in when we get snow or rain... Though the last few years it seems like SW flows have been more dominant in the PWN compared to W, and NW... with high pressure riding becoming more frequent.
I've lived in the BC interior all my life... And while higher elevation mountain snow has remained consistent... it's the lower elevation snow pack that seems to be establishing later, melting earlier and more frequent freeze/thaw cycles through mid-winter.
My hometown hill back in the day was Mt Shasta ski park, wonder how much longer they can stay in business without opening for holiday periods etc. They're finally opening this week without much terrain, such a weird paradox, terrible resort skiing but such great BC access and altitude there.
Yeah man. They've had a really rough time of it the last few years for sure.Quote:
Originally Posted by snapt
We see it here too with our little hills at low elevation, I feel for the new owners of Soldier Mountain, missed out on the holidays due to lack of snow/warm storms etc.Quote:
Originally Posted by LightRanger
Interesting stuff but I'm not sure the problem lends itself to such simplistic modeling or that the errors tend to cancel themselves out. My non-scientific observation has been that Mt. Baker Area has actually benefitted from climate change in some ways. Yes, there are more rain events but warmer temperatures appear to have increased snowfall events during colder weather patterns resulting in more snow during periods that would historically have been cold and dry. This could be due to more overall moisture in the atmosphere.
Also, if I understand your model, it is based upon three recent years having been an average of 2.6 degrees warmer than the historical norm. Weather is highly variable. I believe that for a temperature deviation to be statistically significant it would need to include many more than three years. In other words, the 2.6 degree difference appears to be a number simply pulled out of a hat. And even without any global or regional warming trend, it's normal for snowfall amounts to vary dramatically from year to year. I'm curious, have you explored a particular years average temperature to verify that it is positively correlated to snowfall amounts?
Using average annual temperature deviations from the entire contiguous U.S. when discussing PNW winter snowfall seems rather crude. Global warming affects different regions differently and different seasons differently. I think global warming has disturbed the normal flow of the jet stream and caused the PNW to experience more winter weather that has dropped down from the Gulf of Alaska. It's possible that global warming has increased PNW snowfall as much as it has decreased it. At least for the time being and in certain locals. And that's assuming the PNW region has actually warmed from historical norms which is not clear from the continental data sets you used. Have the average PNW winter temperatures actually warmed?
I know modelling such complex processes based on a few data sets is necessarily imprecise. My thought is that trying to predict snowfall deviations based on the limited data sets you used is perhaps an interesting exercise but ultimately not correlated to the physical world in any meaningful way.
What I find more interesting is how otherwise intelligent beings can deny that human activity has, and will continue to, alter the global climate in an alarming and unacceptable manner. My personal belief is that the climate will reach a tipping point and that the changes we will see in our lifetime will be far more dramatic than even the most alarming scientific projections have predicted.
that's my fearQuote:
Originally Posted by AweShuksan
exposed earth warms fast and holds heat energy that snow cover reflects, it's exponential as the lower elevation snowpack(much larger acreage than mt. tops) recedes
There's some truth here. I think the easiest note is that warmer temperatures have a higher absolute humidity. In our case I think you would get around a 5% increase in water based on the increased temperature alone. It's enough to slightly dampen the effects, but not reverse them. You could argue the overall weather patterns would change in our favor, but that is all speculation, there is no data to really support one way or the other at this point. Just as likely the weather patterns stay the same or make it even worse.Quote:
Originally Posted by AweShuksan
The last 3 years are not an anomaly, they've followed the same trend we've seen over the long term. If you look at the total global warming in a larger sense, it would be closer to 1C, or just under 2F. This number will always lag the most recent values if we are in a continuing trend. There's no argument that we have not been warming, but you could use different values for this warming to explore different scenarios. I think all would be directionally similar.Quote:
Originally Posted by AweShuksan
Yes. Look at the below animation, year to year the warming has not been uniform as expected, but it's all warmer. PNW looks warmer than the global average over the past 5 years. If I used regional numbers they would have been even warmer than what I have, but then we are arguing we need less temporal resolution and higher spatial resolution, and I don't see an obvious reason to do that.Quote:
Originally Posted by AweShuksan
https://svs.gsfc.nasa.gov/4546
My claim would be warmer temperatures correlate to lower snowfall, especially at lower elevations. I don't think this is controversial or even all that insightful. The absolutes have some conversation, but if you see no correlation with that I don't think different math will do much.Quote:
Originally Posted by AweShuksan
I didn't go here because I didn't want to speculate. Although it may be true, there's no science behind a tipping point, and the argument that humans have warmed the atmosphere, although strong, is harder to prove than getting agreement that we have already warmed. I think the pushback on a lot of climate science is a belief system as you noted, it was the reason to abstract some of that and do math, get away from some of the politics/beliefs. In this case, we're arguing a tipping point based on anthropogenic warming, but struggle to agree that warmer temperatures already observed have led to less snowfall.Quote:
Originally Posted by AweShuksan
"...What does this mean for snowfall in the Pacific Northwest?..."
"...This [predicted deviation in snowfall] puts many of the ski areas in the Northwest out of business..."
You seem to conclude that a future deviation from a 20th century average temperature means that Northwest ski areas will experience a deviation between their supposed business success in the 20th century and their future business success. This conclusion does not follow from the data analyzed, because the Northwest ski areas were not even in business at all when averaged over the full duration of the 20th century. If you want to compare 2 periods of business success, the baseline period should be chosen such that business was actually attempted for the duration of the baseline period.Quote:
Originally Posted by cmor
Don't be stupid.Quote:
Originally Posted by Vitamin I
The diminishing snow is a reality and given the trend, it does not look good for the region.
Sent from my SM-G930T using TGR Forums mobile app
It's a good point that the ski business started in the latter half of the century, the analysis is showing the deviation from the century as a whole. For most of us we have not experienced this claimed reduction in snowfall in terms of something we could track, it's already occurred. I think that's why the numbers are bigger than what I would have expected, it's closer to say this is comparing an average 1950 year to 2018. I don't know if the out of business comment is accurate, I would say at risk might be a better term when referring to an additional 1C of warming.Quote:
Originally Posted by Vitamin I
Thoughts on the Pacific Decadal Oscillation and it's affects on comparing numbers over the past few decades to numbers from the 50s-70s? Especially "20th century norms", a century that had two rather cold oscillations. It seems that the average could have been skewed cooler during some of these colder oscillations, which could possibly return.
As for "don't be stupid its happening", I think we all know that. I'm not arguing that human influenced climate change isn't happening and that it needs to be fixed as quick as we possibly can, but also wondering if things like this are skewing our predictions a little more doomsday than they actually should be?
http://research.jisao.washington.edu/pdo/
WTF, retard? Blame someone for citing an evidence based trend?Quote:
Originally Posted by fullStack
Sent from my SM-G930T using TGR Forums mobile app