OR MORE DAMNED LIES FROM THE LUNATIC FRINGE.
This post is a follow-up on my very first blog posting regarding the snow extent.
The reason why I’ve decided to move this forward, is because of the many misconceptions about what is occurring, what did occur and what never happened. Recently, an e-mail came to light about one person’s belief about the rising sea-level. I don’t know if this was meant for public consumption or not, but its out there now, so no use pretending it didn’t happen. You can read about it here. There is a common thought in the scientific world is the hydrological budget is fairly fixed. That is to say, we don’t gain or lose the total amount of water, but rather it takes various forms. A decent general read can be found here.
Given this level of understanding, it’s pretty easy to see why some people get very alarmed about melting snow and ice. Sea levels aren’t rising because we’re creating more H2O, sea levels are rising because of the movement of H2O from solid to liquid, or ice to water. Going back to the e-mail, it seems our Mr. Miller tracked some sea level information and believed it without investigating further. In his defense, sea-level data is tricky and the case is easily made for a dramatic rise in the rate of sea-level rise. (If one desires to misinform.)
Briefly about why sea-level is tricky……… many of us consider sea-level like a tub full of water, uniformly rising as it fills. It doesn’t work that way. It raises in some places and lowers in others, a good illustration of this dynamic can be seen here.
I won’t get into my thoughts about the whys and wherefores about this dynamic, but for our purposes, we can just accept this occurs. Worse news about sea-level, there are a multitude of data sets and a myriad of different recording devices. There is no uniformity when discussing sea-level rise, so when someone asserts they know what the rate of rise is, call them on it. It isn’t possible to reach that level of certitude. Here’s what most people generally agree upon. In a warmer world, we should expect higher sea levels. And, in spite of the team’s best efforts to disappear the MWP and LIA, we can see that they did occur and it wasn’t localized to Greenland or NW Europe. So, coming out of a LIA, we see a modest rise in sea-levels. I may post on the evidence for that MWP and LIA on a later date.
So, what’s this got to do with snow extent? One of the causes of sea-level rise in a warmer world would be moving the H2O from solid(snow and ice) to liquid(water), thus causing sea-level rise.
Lately, we’ve had it drilled into our brain that the snow extent is rapidly declining. We earlier showed that the declining snow extent in spring wasn’t very dramatic, but, that’s where it got left. Today, I’ve decided to investigate further as to whether we’re losing snow extent or not………..
First, let’s update the spring snow extent graph, because we’ve got another years worth of data. Here it is over the last twenty years.
No, not very scary, still. Now, I know this won’t alleviate the fear of the next impending water world, so I’ll dig a bit deeper. We can trot out a graphic Steve Goddard likes, (only we’ll do it over the last 20 years) the NH Winter Snow extent.
Here, we see a much more dramatic slope………… in the opposite direction!!! But that doesn’t give us a full picture. If the snow is melting and we’re getting more in the winter than we are decreasing in spring, then fall should be losing snow also…….
Hmmm…….. err….. WUWT? Fall is increasing in snow extent, too! Okay, so for the finale, let’s look at the total Fall, Winter, and Spring NH snow extent for the last twenty years.
Oh, turns out we’re not really losing our snow extent. What does this tell us? …….not much really. Except, we know what isn’t happening. We’re not losing our snow extent and the loss of snow extent isn’t causing sea-level rise. (At least in the Northern Hemisphere) Any claim otherwise is simply a fabrication. As an afterthought, for you non-believers…..(you know who you are) here’s the entire 20 year monthly history and trend.
Now, can we dispense with the fallacy of our declining snow extent? It did decline, just not in the last 20 years.
Some caveats, explanations, and answers to questions posed. First, I only used Fall, Winter, and Spring because these are the graphics GSL uses and I wished to stay within that particular convention, and I’m not sure what Summer extent would mean, except that I’d be very concerned about a rapidly increasing snow extent during the summer. My seasonal delineations were as follows: Fall, I used Sep, Oct. Nov, Winter, Dec, Jan, Feb, Spring, March, April, May. This may be different from GSL’s. GSL, my source, is RUTGERS UNIVERSITY :: CLIMATE LAB :: GLOBAL SNOW LAB The data may be found here. All values are in square kilometers. Dates are in the format of yyyy mm. I used MS Excel to generate the graphs. I only used NH data because I haven’t found any reliable SH data. Perhaps someone knows of some place where we can get our hands on SH data and would leave us link?
Lastly, I’m suppose to have internet hooked up at my house tomorrow. I’ll be a bit more responsive than I have been lately. Thanks for reading. Feel free to make comments, questions, and critiques.