Home |
Search |
Today's Posts |
![]() |
|
uk.sci.weather (UK Weather) (uk.sci.weather) For the discussion of daily weather events, chiefly affecting the UK and adjacent parts of Europe, both past and predicted. The discussion is open to all, but contributions on a practical scientific level are encouraged. |
Reply |
|
LinkBack | Thread Tools | Display Modes |
#31
![]() |
|||
|
|||
![]()
On Mar 20, 5:19*pm, "Alex Stephens Jr"
wrote: "Dawlish" wrote in message ... What you are doing is trying to push a cold agenda and now you are trying to say that H2O and not CO2 is the reason why Climate is changing. I have no agenda, I wonder why you infinitely persist in saying otherwise.. Look elsewhere for a warming denialist. By the sheer nature of physics and chemistry, positive feedback is already underway. Indeed it's always happening. What temperature would the surface of the earth be if there was no H20 in the atmosphere? Warmer or colder? I wonder if you know the answer to that simple question? The atmosphere is now warmer than at any stage of the previous 100 years so can therefor retain more water vapour. This is a powerful force, initially affecting weather and in turn the climate. If global warming is uniform, then so equally is positive feedback. But, alas, and this may come as somewhat of a surprise to you, there's a tipping point, so special is that little H20 molecule without which bioligcal life would be devoid on this blue oasis in space. Enter the realms of negative feedback, or indeed, not so much a blue oasis in space, more of a white one. One whether through cloud or ice cover reflects solar energy back into space. A drastically cooler planet awaits eventually, again and again and again. Until such times as the sun begins to expand and all life ceases on our planet permanantly. If Carbon Dioxide increases on the planet (or anyother greenhouse gas) to the extent that it's effect counter balances negative feedback, then the future populations of the planet have a problem. A classic runaway greenhouse effect. This line has not been crossed, which is why we have global warming conferences, because there is time to halt such a scenario.. What level of CO2 in the atmosphere constitutes the dividing line? It's a long way off yet. In the meantime the climate changes and this affects most species of life on the planet, not just humans. And the warmer it gets, the more water goes up into the atmosphere and the more falls on Dawlish. Or does it? Strangely the hadley predictions don't seem to think so. I'm sure I read that precipitation in London is forecast by them to increase 0.1% by the year 2050. Why would this be in an atmosphere that is forecast to hold more water vapour? A change to a less maratime and more continental climate perhaps? More snow for Lawrence in winter and more heat for the snow haters in Summer? Anyway, I'm sidetracking... I have no agenda, if you can't accept that then that's your problem I'm afraid. A quick glance at average northern hemisphere land temperatures for the past winter shows that it was on the cooler side of average (just) of the last thirty winters. So, contrary to what you said, it may indeed have been a record warm winter in some parts of the northern hemisphere (land), but it was more than balanced by those who experience a colder than average winter when compared to the thirty year mean. It was certainly not remarkable though in terms of cold hemispherically.... The winter of 2000/01 and moreso the winter of 1993/94 were distinctly colder. What was remarkable was the extended displacement of typical weather patterns. To ask, or to ponder whether that was in any part due to global warming, changing levels of water vapour, shifting oceanic currents or merely just a chance freak of nature is not unreasonable, nor does it amount to jumping on a global cooling bandwagon. And note that I ask these questions, I do not say they are statements of fact. Lex ;-) I argee with much of what you say Lex and of course, negative feedbacks could have begun to occur already - however the last little bit about the northern hemisphere warmer areas being balanced by the colder areas (which would produce an average Northern Hemisphere winter temperature) would take some proving against even a 30-year mean! I'd like to see your figures on that one. Good to see you have no agenda. See how your future posts on the subject stack up in that respect! |
#32
![]() |
|||
|
|||
![]() "Dawlish" wrote in message I argee with much of what you say Lex and of course, negative feedbacks could have begun to occur already - however the last little bit about the northern hemisphere warmer areas being balanced by the colder areas (which would produce an average Northern Hemisphere winter temperature) would take some proving against even a 30-year mean! I'd like to see your figures on that one. Good to see you have no agenda. See how your future posts on the subject stack up in that respect! Just a quick reply, I stated that northern hempisphere LAND temperatures this past winter were lower than the average of the last 30 years. Not including oceanic temperatures of course. I took the figures from the ncdc website, which seems a fairly reliable source. ftp://ftp.ncdc.noaa.gov/pub/data/ano...1-2000mean.dat The figure given for each winter is the deviation from the whole dataset average I believe (winter being the December of the previous year, averaged with the January and February of the stated year). Or perhaps it's the deviation from that dastardly 1951-1980 mean that keeps cropping up. Either way, it shows that the past winter was marginally cooler than the most recent 30 year mean. The Winter's of 2001 and 1993 stand out as being colder during the last 10, and the winter of 1985 clearly the coldest of them all. Note that the last three values show a plateau, two or more subsequent values may indicate a trend of warming suspension (as far as NH land winters are concerned). But we have to wait two years to see if that will be the case. 1980.0 0.8 1981.0 0.8 1982.0 0.2 1983.0 0.7 1984.0 0.1 1985.0 -0.6 1986.0 0.4 1987.0 0.5 1988.0 0.5 1989.0 0.5 1990.0 0.6 1991.0 0.7 1992.0 0.9 1993.0 0.7 1994.0 0.0 1995.0 1.1 1996.0 0.4 1997.0 0.8 1998.0 0.8 1999.0 1.3 2000.0 1.4 2001.0 0.3 2002.0 1.4 2003.0 0.7 2004.0 1.3 2005.0 0.6 2006.0 0.8 2007.0 1.4 2008.0 0.6 2009.0 0.9 2010.0 0.6 average 0.7 ;-) |
#33
![]() |
|||
|
|||
![]() "Alex Stephens Jr" wrote in message ... "Dawlish" wrote in message I argee with much of what you say Lex and of course, negative feedbacks could have begun to occur already - however the last little bit about the northern hemisphere warmer areas being balanced by the colder areas (which would produce an average Northern Hemisphere winter temperature) would take some proving against even a 30-year mean! I'd like to see your figures on that one. Good to see you have no agenda. See how your future posts on the subject stack up in that respect! Just a quick reply, I stated that northern hempisphere LAND temperatures this past winter were lower than the average of the last 30 years. Not including oceanic temperatures of course. I took the figures from the ncdc website, which seems a fairly reliable source. ftp://ftp.ncdc.noaa.gov/pub/data/ano...1-2000mean.dat The figure given for each winter is the deviation from the whole dataset average I believe (winter being the December of the previous year, averaged with the January and February of the stated year). Or perhaps it's the deviation from that dastardly 1951-1980 mean that keeps cropping up. Either way, it shows that the past winter was marginally cooler than the most recent 30 year mean. The Winter's of 2001 and 1993 stand out as being colder during the last 10, and the winter of 1985 clearly the coldest of them all. Note that the last three values show a plateau, two or more subsequent values may indicate a trend of warming suspension (as far as NH land winters are concerned). But we have to wait two years to see if that will be the case. 1980.0 0.8 1981.0 0.8 1982.0 0.2 1983.0 0.7 1984.0 0.1 1985.0 -0.6 1986.0 0.4 1987.0 0.5 1988.0 0.5 1989.0 0.5 1990.0 0.6 1991.0 0.7 1992.0 0.9 1993.0 0.7 1994.0 0.0 1995.0 1.1 1996.0 0.4 1997.0 0.8 1998.0 0.8 1999.0 1.3 2000.0 1.4 2001.0 0.3 2002.0 1.4 2003.0 0.7 2004.0 1.3 2005.0 0.6 2006.0 0.8 2007.0 1.4 2008.0 0.6 2009.0 0.9 2010.0 0.6 average 0.7 ;-) I should also add, that if the NH winter land values for 2011 and 2012 do form a suspended trend (compounding seven of the last eight winters) whilst the corresponding ocean temperatures continue warming - it would be significant evidence of negative feedback. Complex theoreticity :-) |
#34
![]() |
|||
|
|||
![]()
On 20/03/10 09:41, Will Hand wrote:
Speaking purely as a mathematician (which is my degree qualification), if a trend reverses, then it will take time for subsequent events to return to a long term value. So I am not surprised that the NH winter was 13th warmest, but perhaps if the GW temperature trend had still been on the up at the same rate is was a few years back then perhaps it should have been the fourth or such. OTOH if GW had not happened then last winter might have been the 100th. Only time will tell, but I think what Alex is alluding to is that last winter probably came as a shock to climate scientists! I still think too much has been made of the recent levelling-off of global temperatures. Looking at an 11-yr running mean, it is no more noticeable - at least so far - than any of the pauses that have been happening every 7-8 years since 1970, in fact rather less so than a couple of them. This is also true when looking at 5-yr means. The last 12-month period was the warmest on record for the March to February period at +0.61C, beating the previous highest of 2005-6 by just 0.01C with 2006-7 in third place at +0.58C. When looking at any 12-month period, the highest was that ending in December 2005 at +0.63C, followed by those ending in July and August 2007 at +0.62C. -- Graham P Davis, Bracknell, Berks., UK. E-mail: newsman not newsboy "I wear the cheese. It does not wear me." |
#35
![]() |
|||
|
|||
![]()
On Mar 20, 8:37*pm, Graham P Davis wrote:
On 20/03/10 09:41, Will Hand wrote: Speaking purely as a mathematician (which is my degree qualification), if a trend reverses, then it will take time for subsequent events to return to a long term value. So I am not surprised that the NH winter was 13th warmest, but perhaps if the GW temperature trend had still been on the up at the same rate is was a few years back then perhaps it should have been the fourth or such. OTOH if GW had not happened then last winter might have been the 100th. Only time will tell, but I think what Alex is alluding to is that last winter probably came as a shock to climate scientists! I still think too much has been made of the recent levelling-off of global temperatures. Looking at an 11-yr running mean, it is no more noticeable - at least so far - than any of the pauses that have been happening every 7-8 years since 1970, in fact rather less so than a couple of them. This is also true when looking at 5-yr means. The last 12-month period was the warmest on record for the March to February period at +0.61C, beating the previous highest of 2005-6 by just 0.01C with 2006-7 in third place at +0.58C. When looking at any 12-month period, the highest was that ending in December 2005 at +0.63C, followed by those ending in July and August 2007 at +0.62C. -- Graham P Davis, Bracknell, Berks., UK. *E-mail: newsman not newsboy "I wear the cheese. It does not wear me." Keep your eye on the 12-month period starting in either May, or June, 2009 Graham. If Global temperatures stay high - and slow global temperature decay from this El Nino is highly likely to keep those temperatures high, one of those two periods is likely to be a record, global, 12-month temperature high. |
#36
![]() |
|||
|
|||
![]()
On Mar 20, 7:19*pm, "Alex Stephens Jr"
wrote: "Dawlish" wrote in message I argee with much of what you say Lex and of course, negative feedbacks could have begun to occur already - however the last little bit about the northern hemisphere warmer areas being balanced by the colder areas (which would produce an average Northern Hemisphere winter temperature) would take some proving against even a 30-year mean! I'd like to see your figures on that one. Good to see you have no agenda. See how your future posts on the subject stack up in that respect! Just a quick reply, I stated that northern hempisphere LAND temperatures this past winter were lower than the average of the last 30 years. Not including oceanic temperatures of course. I took the figures from the ncdc website, which seems a fairly reliable source.ftp://ftp.ncdc.noaa.gov/pub/data/ano....00N.90N.df_19... The figure given for each winter is the deviation from the whole dataset average I believe (winter being the December of the previous year, averaged with the January and February of the stated year). Or perhaps it's the deviation from that dastardly 1951-1980 mean that keeps cropping up. Either way, it shows that the past winter was marginally cooler than the most recent 30 year mean. The Winter's of 2001 and 1993 stand out as being colder during the last 10, and the winter of 1985 clearly the coldest of them all. *Note that the last three values show a plateau, two or more subsequent values may indicate a trend of *warming suspension (as far as NH land winters are concerned). But we have to wait two years to see if that will be the case. 1980.0 * *0.8 1981.0 * *0.8 1982.0 * *0.2 1983.0 * *0.7 1984.0 * *0.1 1985.0 *-0.6 1986.0 * *0.4 1987.0 * *0.5 1988.0 * *0.5 1989.0 * *0.5 1990.0 * *0.6 1991.0 * *0.7 1992.0 * *0.9 1993.0 * *0.7 1994.0 * *0.0 1995.0 * *1.1 1996.0 * *0.4 1997.0 * *0.8 1998.0 * *0.8 1999.0 * *1.3 2000.0 * *1.4 2001.0 * *0.3 2002.0 * *1.4 2003.0 * *0.7 2004.0 * *1.3 2005.0 * *0.6 2006.0 * *0.8 2007.0 * *1.4 2008.0 * *0.6 2009.0 * *0.9 2010.0 * *0.6 average * 0.7 ;-) Thanks Alex. It looks like we have a 30-year balance! Would you post the NOAA source again, as I can't get the link to work. |
Reply |
Thread Tools | Search this Thread |
Display Modes | |
|
|
![]() |
||||
Thread | Forum | |||
Joe B spot again! | uk.sci.weather (UK Weather) | |||
Joe again | uk.sci.weather (UK Weather) | |||
Joe again | uk.sci.weather (UK Weather) | |||
Joe again | uk.sci.weather (UK Weather) | |||
Joe Bastardi's Europe Column | uk.sci.weather (UK Weather) |