|
|
Post by karlox on Dec 6, 2012 9:15:48 GMT
Nautonnier, and these cells become less vigorous or drop towards the equator due to... less temperature gradient between tropical areas and poles? Is it the same in South Hemisphere at this same times? We, in Spain are within eastern edge of blocking high, cold but don´t get hit straight forward by the polar jet streams as UK is been... but true that it is a prettly repetitive pattern with little oscillations... Put a large pan of water over a small burner and as it comes to the boil you will see the convection in the water causing a hump over the burner the water rises up in the middle and runs to the cooler water. This is just what the equatorial Hadley cells do - yes both sides of the equator. See:  If the heat is turned up - then the Hadley cells grow and push the Ferrel cells poleward. The Ferrel cells are the location of the temperate latitudes weather systems. There are jet streams between the Hadley and Ferrel cells and between the Ferrel cells and the Polar cells. These are not completely symmetrical and the jets meander with Rossby waves in them. If the Hadley cells become less active then they shrink and the Ferrel cells move equatorward and are followed by widening of the polar cells. At the moment it would appear that the convective activity of the Hadley cells has reduced and we see weather in the Ferrel cells moving equatorward. The jetstream that delineates the boundary between the cells has become loopy with a lot of meridonal flow and blocking highs (sometimes called omega highs due to the shape forced in the jetstreams) stop the waves in the jetstream leading to continual weather of the same type over some areas for months. If you are lucky you are in the nice weather part  Of course the question of the decade is what increases or reduces the Hadley cell convection? It seems to be a feedback between ocean and atmospheric temperatures causing or limiting cloudiness, but as the oceans get hot causing more cloud the cloud reduces the heat into the oceans the humidity causing the clouds alters the enthalpy of the air and the ratio between dry and wet adiabatic lapse rates that governs the strength of convection..... so its a multiple positive and negative chaotic feedback loop. And the atmosphere and the oceans are both moving at different rates carrying heat to different areas - in the atmosphere this heat transport is largely as latent heat of water vapor and water droplets being carried to different areas. In the oceans there is a far more ponderous and slow thermohaline circulation carrying warm or cold water around a centuries long track with upwelling and downwelling currents. Then add length of day changes and tides slopping both the sea and atmosphere and things rapidly turn into an nP problem. This is not conducive to drawing a straight line projection from past through current values to forecast the future. Yet that is what a lot of people are doing. Many thanks for your pedagogic effort to me! I now realized you already gave me this lesson on Cells in the past, a couple of years ago, and well, I think I know understand it much better that then... so for sure something I´ve learned these years! I´ve also re-read Svenkmark´s theories on Cosmic Rays... you for sure know... I would like to have your own opinion on that approach, and if something new has arisen lately regarding that theory... Thanks in advance again! |
|
|
|
Post by nautonnier on Dec 6, 2012 16:30:33 GMT
An interesting forecast from Joe Bastardi - where he talks of the loopiness of the Jetstreams www.weatherbell.com/fitch/index.php?cmd=homepageIt should be remembered that although the diagrams show nice solid jet streams the reality is somewhat different. They meander and break, small jetstreams sometimes called jetstreaks appear. The atmosphere is not a nice mathematically ordered layered entity, it is a chaotic fluid more akin to a lava lamp with swirls and breaking waves in the tropopause. As I tried to say it is also affected by many inputs - cloudiness could come from galactic cosmic rays as well as from convection. Albedo from ice and cloud tops. Clouds can form by warm humid winds over cold water and by convection of water vapor from warm water into cold air. In fact still air over water with both at the same temperature will result in slow convection and clouds as water evaporates and humid air is lighter than dry air. The insistence that a particular variable is THE one that causes anything cannot ever be correct. |
|
|
|
Post by karlox on Dec 6, 2012 19:33:26 GMT
An interesting forecast from Joe Bastardi - where he talks of the loopiness of the Jetstreams www.weatherbell.com/fitch/index.php?cmd=homepageIt should be remembered that although the diagrams show nice solid jet streams the reality is somewhat different. They meander and break, small jetstreams sometimes called jetstreaks appear. The atmosphere is not a nice mathematically ordered layered entity, it is a chaotic fluid more akin to a lava lamp with swirls and breaking waves in the tropopause. As I tried to say it is also affected by many inputs - cloudiness could come from galactic cosmic rays as well as from convection. Albedo from ice and cloud tops. Clouds can form by warm humid winds over cold water and by convection of water vapor from warm water into cold air. In fact still air over water with both at the same temperature will result in slow convection and clouds as water evaporates and humid air is lighter than dry air. The insistence that a particular variable is THE one that causes anything cannot ever be correct. For what I understand from theory on galactic cosmic rays would rather be that a certain "modulation" of cloudiness, thus affecting albedo and lower temparatures (low clouds), is triggered by cosmic rays -other than solar wind- which reach more easily our planet during long periods of weak solar activity... such as it would be the case now... so it would be just another hint on how such a chaotic system as our atmosphere and climate could also be driven by extraterrestrial influence... that´s how I got it.... But, is there any new research on this? Is it being more accepted now by the scientific community? For I understood it is just a theory -probably well founded - but a theory I am not capable of judging as important or not. Thanks! |
|
|
|
Post by sigurdur on Dec 7, 2012 3:35:58 GMT
|
|
|
|
Post by Pooh on Dec 7, 2012 6:56:26 GMT
|
|
|
|
Post by karlox on Dec 7, 2012 8:37:55 GMT
Thanks Pooh!  It will take me some time... I am not an english native speaker, and my "hearing" is getting worse with climate change, sorry I meant age ;D Meanwhile, what do you think about it? |
|
|
|
Post by Pooh on Dec 7, 2012 20:33:06 GMT
.... Meanwhile, what do you think about it? Plausible, but not a conclusive explanation of every loose end. E.g., some but not all of the explanation for global temperature fluctuation -- a contributor. There has been at least one study claiming no "correlation" between clouds and sunspot number. I do not recall any mention in that paper of "lags" between solar activity and the CLOUD effect; it is a long way to the magnetopause, even at the speed of the solar wind. If GCR are 'braked' by magnetic fields, it would be a long, slow process. I'll have to update myself from Kirkby's recent work. |
|
|
|
Post by karlox on Dec 8, 2012 11:28:42 GMT
astroposer, No one has a handle on the next event. We can't do much to prepare for a NEO or Supervolcano but we can and probably should have some sort of national plan in effect for realistic dangers that have happened and will happen again in the not so distant future. The famine of 1315 was caused by three excessively wet springs and cool summers in Europe. Even with modern technology I doubt world wide food supplies could hold up to some of the extreme weather events that would likely accompany an abrupt shift from our current warm to a colder cycle. The threat becomes much more severe if combined with other events like a global pandemic or massive solar storm powerful enough to disrupt our electrical grid. The global economy is pretty week and Im not sure it can stand on its own if everything remains the same. Add a global pandemic or heaven forbids a "perfect storm" of natural disasters into the equation and the results could get nasty. Yes indeed! We -as a global civilization- as become somehow much mure vulnerable as most part of mankind are pieces of a mulidependance economic and social scheme... and food supply, food future markets, famine spreading etc are much more likely to happen now than ever... our crisis to come are closely bounded to the exponential rate of growth and stress we are putting in our planet... systems grow and fall... (and evolve) So where are we now?  |
|
|
|
Post by karlox on Dec 8, 2012 11:30:05 GMT
Sorry for the mispelled words of previous post! (Am I mispelling now?)
|
|
|
|
Post by sigurdur on Dec 8, 2012 11:32:03 GMT
karlox: Your spawling is fine. We are not here to spell check posters.... |
|
|
|
Post by sigurdur on Dec 8, 2012 11:36:17 GMT
Where are we now?
We know we are approaching the temperature metrics of the MWP.
We know we are approaching Arctic Ice conditions last documented to have occured during the MWP.
Are we at the end of the warmup per se? Transitioning to a cooler climate?
I, for one, don't know. I do know that during past times of similiar conditions the SW of the USA turned dry.......very dry. The central plains also had a very dry bias.
The USA is experiencing condtions that are very simliar to the 1930's, the early stages of a multi year drought.
|
|
|
|
Post by karlox on Dec 8, 2012 12:24:22 GMT
Got the "feeling" it won´t be so but -hope- but rather whatever weather we had well advanced a very weak solar cycle like this and weaker next one expected according to experts... we are right on the middle of a weather shift... and temps and precps of this winter-fall will probably show better the coming trend... But checking closest paired well-founded-data weak cycle could be a hint on this unknown coming trend for next years...
|
|
|
|
Post by karlox on Dec 8, 2012 12:27:10 GMT
so I guess I´ve become a "believer" of a ´more-than-thought-before of sun influence on our weather and climatic oscillations´ but I don´t like what we do to our atmosphere and oceans anyhow.
|
|
andor
Level 2 Rank
Posts: 60
|
Post by andor on Dec 8, 2012 12:59:16 GMT
Even for me as an oil-worker it's clear that we are entering a cool period! Just look at the sunspot trend!!! I know anything could still change but the trajectory is clear. It could be a fast trend down by December 21st?
What more could the NWO wished for? Natural disaster diminishing the world's population?
|
|
|
|
Post by sigurdur on Dec 15, 2012 17:09:28 GMT
Helping out thermostat here and re-posting the link from above: www.agu.org/pubs/crossref/2011/2011GL049444.shtmlThis is a very recent re-construction of the temps from Greenland. Now that we know the current warmth is NOT anything exceptional, can we continue a robust discussion and search for more pertenant literature? |
|
