Onderstaande artikel vond ik op
http://www.landscheidt.info/?q=node/189
Wat mij betreft interessant om te lezen. Nu vraag ik me een paar dingen af.
1) Wetenschappelijk goed onderbouwd?
2) Hij geeft aan dat de NAO in december wel eens erg laag kan worden, kent iemand daarvan onderzoek?
3) Hoe kan de NAO voorspeld worden?
4) Relatie NAO en PDO, weet iemand daar goed onderzoek over?
Bedankt!
A Massive Winter Heading for the Northern Hemisphere?
Posted Sun, 07/25/2010 - 01:25 by Geoff Sharp
PART 1
The winters of the past two years have been noticeably colder. The northern hemisphere in particular has experienced record cold, record snow and a rebuilding of the Arctic sea ice extent. The southern hemisphere this winter has also seen record low temperatures in South America which is resulting in many hundreds of deaths (human and livestock).
There are a number of players involved which can be attributed to this cooling trend and when they come together they are capable of dropping the world's temperatures by a significant amount.
Perhaps the most important player is the Pacific Decadal Oscillation (PDO) which is a hot and cold ocean temperature cycle in the Pacific of about 30 years. The world's temperature trend very closely matches this cycle which has the potential to override solar activity of the day. The last major PDO cooling event was between 1946 and 1976 which experienced the highest solar cycle on record (SC19) followed by a low cycle (SC20). The deepest cold of this era was recorded when both the PDO and low solar activity teamed up, which is right where we are again today with perhaps a greater influence from the solar side with my predicted imminent grand minimum.
New research is suggesting the solar influence on climate/weather is not just about the overall heat output of the Sun which varies very little, but more about the atmospheric effects from extreme ultraviolet radiation (EUV). EUV can vary by as much as 16% over the solar cycle and this last solar minimum has seen the levels a lot lower than the previous solar minimum. EUV does it's thing in the upper atmosphere where it heats the Thermosphere and also creates Ozone, currently NASA is reporting the lowest recorded height of the Thermosphere and is at a loss at explaining all of the contributing factors. Others like Mike Lockwood are linking lower UV rates with changes in the polar jet streams that form a blocking effect on the normally warmer winds that occur in the northern hemisphere winter.
Aside from other ocean oscillations the ENSO [cool pacific] pattern has a large short term effect on our climate/weather system. We are just coming out of a rather warm El Nino cycle and current observations are showing the possible impact of a very strong La Nina cooling pattern taking shape.
The La Nina phase is now official with the Australian BOM records showing all the major indicators heading into continued La Nina conditions. Of particular interest is the sub surface temperatures in the Pacific showing a large area 4 deg C under normal.
Another oscillation called the Antarctic aooOscillation (AAO) is showing its highest readings since records began in 1979, during the strong 1999 and 2008 La Ninas the AAO was also high.
The cooling phase of the PDO is just beginning and should reduce the strength and frequency of future El Ninos and add extra punch and frequency to upcoming La Ninas.
Joe Bastardi from Accuweather who is an avid follower of this site is also predicting the same cooling trend, he also adds the possible cooling effects that could result from impending volcanic eruptions.
So the stage is set for one of the most interesting natural experiments, nearly all the cool players are in place with the exception of the Atlantic Oscillation (AMO) still not in its cool phase. I predict the extra boost from my predicted solar grand minimum along with the current oceanic conditions the next northern winter will experience conditions similar to the Little Ice Age (1250-1850).
The North Atlantic Oscillation (NAO) is an atmospheric oscillation resulting from two pressure cells occurring in the Northern Atlantic Ocean and is closely linked with the Arctic Oscillation. During it's positive phase warmer winds are prevalent across the northern hemisphere with an additional blocking effect of the cooler Arctic air mass.
The NAO is very closely aligned with the PDO sharing modulation and phasing and together in their negative phase along with a La Nina cycle are potent team members capable of inflicting significant world cooling.
The NAO/PDO correlation may not be coincidental. Landscheidt (2001) proposed a close link between solar output and the NAO (fig.6) and Scafetta (2010) indicates a correlation between solar velocity and the PDO. Both cycles look to be in sync with the solar/planet dynamics of our solar system. Landscheidt at the time had no physical mechanism but recent research is pointing toward EUV flux as a very likely climate oscillator candidate. The modulation of these climate effects from EUV being so much greater during grand minima. (SC20 at 1970 being very close to a grand minimum). TSI might just be a very small player.
The NAO is showing signs of going negative and is expected to be in full force by December if we follow history. It is reasonable to suggest the same forces were in play with the same timings during the Dalton Minimum. If so I think we can expect a similar weather pattern as of that era, especially if Katla decides to erupt.
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