lin 0 Posted February 26, 2007 Share Posted February 26, 2007 Nice work soubs. I'm a bit surprised to see that last year wasn't especially cold considering the snow. Link to post Share on other sites
soubriquet 0 Posted February 27, 2007 Author Share Posted February 27, 2007 Thanks lin. I've been looking at sea surface temperature (sst). You find data for Japan here: http://www.ocean.caos.tohoku.ac.jp/~merge/sstbinary/actvalbm.cgi?eng=1 SST is important because the heat energy stored in the oceans drives the weather. The steep temperature gradients where different water masses meet, generate and steer the low pressure systems. These are the images for 31st January 2006 and 2007. It's hard with this stuff to determine what is cause and what is effect, but there are some significant features in the images. I think the Pacific is the cause, and the effect is seen in the Sea of Japan. The 2006 image shows Pacific tropical water mass as far north as Chiba, and the Arctic water mass south to Miyagi. 2007 has a warmer Pacific water mass as far north as Miyagi, and a much steeper temperature gradient. What seems to have happened is the lows have been tracking up the Tohoku coast rather than out to sea off Chiba. As a result, the lows have been pumping warm Pacific air from the SE, rather than dragging down Arctic air from the NW. The effect is seen in the Sea of Japan, which has retained much of its heat throught the winter. It will be interesting to see if a warmer Sea of Japan will affect the summer weather, and more importantly, next winter. I'd speculate that there is the potential to generate extra precipitation next winter if the lows revert to their normal path. Link to post Share on other sites
gerard 6 Posted February 28, 2007 Share Posted February 28, 2007 I like the psychadelic pictures. It's hard to tell the causes from the effects. One weather report said that this year, the cold air mass over the arctic never extended as far south as it usually does. There must be a lot more going on though. Quote: What seems to have happened is the lows have been tracking up the Tohoku coast rather than out to sea off Chiba. As a result, the lows have been pumping warm Pacific air from the SE, rather than dragging down Arctic air from the NW (edited--you meant 'NW' right?). That seems to hit the nail on the head. Usually low pressure systems camp out to the east and drag cold air and snow from Siberia and the Sea of Japan. But this year they seem to be coming up from the south or west and crossing directly over Japan more often. Plus, when the weather is stable, the tempuratures seem incredibly high. Anyway, even a bad year in Japan is still pretty good at higher elevations. Link to post Share on other sites
soubriquet 0 Posted February 28, 2007 Author Share Posted February 28, 2007 Oops. Thanks, I meant NE. I've gone back and edited the post. Encouraging to see someone's paying attention I'm really intrigued by the excess heat in the Sea of Japan. It will have do dissipate somehow. When, and by what route are the questions. I'm going to keep monitoring this. Link to post Share on other sites
soubriquet 0 Posted March 1, 2007 Author Share Posted March 1, 2007 I've gone back to the RAW data, extracted the temperature values, and found the difference. This image isn't calibrated, but yellow and red are 2007 warmer than 2006, and green and blue 2007 colder than 2006. The darkest blues are around 4C cooler, and the brightest yellow is 11C warmer. Link to post Share on other sites
griller 9 Posted March 2, 2007 Share Posted March 2, 2007 Interesting stuff soubriquet, though that last image looks kinda angry & scary! Link to post Share on other sites
BagOfCrisps 24 Posted March 2, 2007 Share Posted March 2, 2007 Very interesting soubs. Thanks for putting it together. Link to post Share on other sites
lin 0 Posted March 2, 2007 Share Posted March 2, 2007 Looks like some Doomsday scenario map (not too far from the truth I suppose!) Nice work soubriquet. Curious that Sado off the coast of Niigata is green. Link to post Share on other sites
tsondaboy 0 Posted March 2, 2007 Share Posted March 2, 2007 Good job Soub. Link to post Share on other sites
soubriquet 0 Posted March 3, 2007 Author Share Posted March 3, 2007 Thanks everyone. I'm happy that people are interested. lin, sorry but on land that green is an artefact. In the software I used, that green is a null value. After I saved the image, I used photoshop to change the nulls to black. Having spent half a day extracting the values and finding a way to represent them clearly (+ve vs -ve), I couldn't be arsed to flood every island. Oops Data are for 31st Janaury, both years, btw. Link to post Share on other sites
sunrise 0 Posted March 3, 2007 Share Posted March 3, 2007 The interesting thing about this is that the oceans around Sydney are uncharacteristically cold this year. Link to post Share on other sites
lin 0 Posted March 5, 2007 Share Posted March 5, 2007 I see. Data for Feb would be interesting things really seem to be heating up there this last week. Link to post Share on other sites
snowdude 44 Posted March 5, 2007 Share Posted March 5, 2007 Very interesting data! Actually this year we are in for a scorcher, unfortunately, more like a traditional summer. But before that kicks in we are in for another nice cold snap from around Tuesday next week and that should continue for at least the next two weeks, dumping some snow around, even at the lower elavations. Looking at all the data and studying the weather patterns over the last few months, I predict next winter 2007/08 is going to be a snowy and cold one. A bit early to tell yet for sure, but several factors are pointing in that direction. Link to post Share on other sites
skidaisuki 0 Posted March 5, 2007 Share Posted March 5, 2007 Snowdude - I want to believe you, but unfortunately nothing except the law of averages suggests that you might be right. Not even pro forecasters can say with any degree of accuracy. Link to post Share on other sites
grungy-gonads 54 Posted March 5, 2007 Share Posted March 5, 2007 Those really are scary maps soubs. Looks like something rahul (where are his earthquake predictions now?) would post. We will hope you are right snowdude. Surely whatever next season brings it will be better (amount of snow falling-wise) than this season which must be a one off. Link to post Share on other sites
soubriquet 0 Posted March 5, 2007 Author Share Posted March 5, 2007 Quote: Originally posted by griller: Interesting stuff soubriquet, though that last image looks kinda angry & scary! I guess you're right. I hadn't thought about in those terms. I'll put together some stuff for February over the next few days. Now I've worked out how to extract the data and present it, it won't take too long. I'm no Rahul, g-g. I'm using data, not astrological charts I don't have any predictions, because I don't have a model, but I'm very interested to see what effect (if any) the unseasonal heat in the Sea of Japan has this summer. Link to post Share on other sites
muikabochi 208 Posted March 7, 2007 Share Posted March 7, 2007 I haven't heard one of rahuls predictions of late, must mean we are safe from the shakers. Gambatte soubriquet! Link to post Share on other sites
r45 4 Posted March 8, 2007 Share Posted March 8, 2007 Good work soubriquet... keep it coming. It sure will be interesting to see how the spring and summer months go this year. Link to post Share on other sites
soubriquet 0 Posted March 9, 2007 Author Share Posted March 9, 2007 Here is an image of sst difference. This time I've averaged the data from 2003-2006, and subtracted it from the data for 28th February, 2007. Reds and yellows are warmer (up to +8 degrees), and greens and blues colder (to -1.5). Edit. I've substituted a version of the image with a tighter flood. Hokkaido looks a bit better now, cal Link to post Share on other sites
cal 6 Posted March 11, 2007 Share Posted March 11, 2007 A lot of red on that one. Hokkaido has expanded. Did the Australians have anything to do with that? Link to post Share on other sites
big-will 7 Posted March 12, 2007 Share Posted March 12, 2007 I might be missing something really blindingly obvious here but soubs what is "sst difference"? Link to post Share on other sites
soubriquet 0 Posted March 12, 2007 Author Share Posted March 12, 2007 SST is sea surface temperature. The difference is the values I get when I subtract the average values (2003-3006) from the 2007 data. Link to post Share on other sites
big-will 7 Posted March 12, 2007 Share Posted March 12, 2007 Aha, I see. Thanks. Link to post Share on other sites
NutteyCubey 0 Posted March 14, 2007 Share Posted March 14, 2007 Quite conclusive then that. Thanks for the efforts soubriquet. Link to post Share on other sites
soubriquet 0 Posted April 26, 2007 Author Share Posted April 26, 2007 A little belatedly, I've just worked up the data for the end of March. Edit. I found a simple arithmetic error, and have gone through and re-calculated. The original image was sus, this looks much better Everything pretty much as expected. Central Pacific 2 degrees warmer than normal, averaged 2003-2006. The northern Pacific (blue green to black) is slightly cooler than average. Still warmer than average in the southern Sea of Japan and Yellow Sea. I have also run a North to South profile along the eastern margin of the image. This profile gives the actual temperature difference. shows some big pools of cooler than average water east of Chiba. I'd be looking there for summer typhoon activity at the southern end, where the temerature gradient is steepest. Link to post Share on other sites
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