53 replies to this topic

[jethro]

What happens in the skies above? Will a warming world make it cloudier and wetter, will a cloudier world make it colder? Has the quiet Sun driven the Jet Stream off course? What are the negative and positive feedbacks, how will they impact upon the climate? Will more Ozone make us warmer or colder?

[Solar Cycles]

Just posted something in the Spring/ Summer thread, might be more appropriate in here though. Many have noticed that during the last few years Thunderstorms have become less frequent. What are peoples opinion on this maybe being tied in with low solar activity. There as been some research into Thunderstorms and solar activity, but not much in the way of up to date research. Would be interesting to hear all your views, on the correlation of Thunderstorms and solar activity.

[Boar Wrinklestorm]

Changes in severe thunderstorm environment frequency during the 21st century caused by anthropogenically enhanced global radiative forcing

Robert J. Trapp,*† Noah S. Diffenbaugh,* Harold E. Brooks,‡ Michael E. Baldwin,* Eric D. Robinson,* and Jeremy S. Pal§¶

Abstract said:

Severe thunderstorms comprise an extreme class of deep convective clouds and produce high-impact weather such as destructive surface winds, hail, and tornadoes. This study addresses the question of how severe thunderstorm frequency in the United States might change because of enhanced global radiative forcing associated with elevated greenhouse gas concentrations. We use global climate models and a high-resolution regional climate model to examine the larger-scale (or “environmental”) meteorological conditions that foster severe thunderstorm formation. Across this model suite, we find a net increase during the late 21st century in the number of days in which these severe thunderstorm environmental conditions (NDSEV) occur. Attributed primarily to increases in atmospheric water vapor within the planetary boundary layer, the largest increases in NDSEV are shown during the summer season, in proximity to the Gulf of Mexico and Atlantic coastal regions. For example, this analysis suggests a future increase in NDSEV of 100% or more in locations such as Atlanta, GA, and New York, NY. Any direct application of these results to the frequency of actual storms also must consider the storm initiation.

Source, PDF

Edited by VillagePlank, 21 June 2010 - 11:06 .

[Solar Cycles]

VillagePlank, on 21 June 2010 - 11:05 , said:

Changes in severe thunderstorm environment frequency during the 21st century caused by anthropogenically enhanced global radiative forcing

Robert J. Trapp,*† Noah S. Diffenbaugh,* Harold E. Brooks,‡ Michael E. Baldwin,* Eric D. Robinson,* and Jeremy S. Pal§¶



Source, PDF

Thanks VP. Is there anything you have come across, that shows some sort of correlation between solar activity and Thunderstorms?

[Solar Sausage]

Hi guys.

Are we talking about a global decrease in convection or a local one? Would I be right in suggesting that for such a decrease to be solar-driven it would be a necessarily global phenomenon?

[Solar Cycles]

Pete Tattum, on 21 June 2010 - 13:13 , said:

Hi guys.

Are we talking about a global decrease in convection or a local one? Would I be right in suggesting that for such a decrease to be solar-driven it would be a necessarily global phenomenon?

Not necessarily Pete. maybe just the NH.

Edited by Solar Cycles, 21 June 2010 - 15:21 .

[Gray-Wolf]

Let's wait until october and see how the averages work out then? With the size of 'cane season predicted I'd bet the 'average' nudges up a bit!!!

If we lok at the pee poor numbers of 'canes the past 2 years then you'd be thinking (if you were me) that upper level shear has reduced the size of storms......la Nina?

[Solar Cycles]

Gray-Wolf, on 21 June 2010 - 15:40 , said:

Let's wait until october and see how the averages work out then? With the size of 'cane season predicted I'd bet the 'average' nudges up a bit!!!

If we lok at the pee poor numbers of 'canes the past 2 years then you'd be thinking (if you were me) that upper level shear has reduced the size of storms......la Nina?

Blimey GW, never thought I would hear those words from you. "Let's wait and see".

[Boar Wrinklestorm]

Solar Cycles, on 21 June 2010 - 11:38 , said:

Is there anything you have come across, that shows some sort of correlation between solar activity and Thunderstorms?

Here (on page 229, but I recommend you read the preceding pages, first)

Edited by VillagePlank, 22 June 2010 - 08:15 .

[Solar Cycles]

VillagePlank, on 22 June 2010 - 08:07 , said:

Here (on page 229, but I recommend you read the preceding pages, first)

Thanks for digging that one out VP. A very interesting read, looks like there is no correlation between sunspots and thunderstorms. However that report is from 1936, so maybe more evidence will surface to support this. Also I noted the temperature correlations with sunspot activity, some evidence to suggest that fewer sunspots doesn't always equate to lower temps. This for me shows where the oceans play there part, heat stored and then slowly released over time. Now I'm sure I have a paper regarding solar activity and the oceans somewhere, but finding it will prove quite a challenge, with my cluttered filing system!

[Boar Wrinklestorm]

Solar Cycles, on 22 June 2010 - 08:29 , said:

This for me shows where the oceans play there part, heat stored and then slowly released over time.

Yes, I quite agree - and this may form the physcial basis of the LI hypothesis. I am currently doing the research that might tie ocean current temerpatures with atmospheric temperatures which are driven by solar activity - or, as that piece argues, since the Earth's magnetic field correlates extremely well with sun activity - there is virtually no difference from using either as a source.

Briefly, you treat the heating of the ocean, and it's subsequent release of heat later on in the same way that you might value inventory - ie FIFO. Various known physical mechanisms, such as the conservation of energy, are all involved.

Edited by VillagePlank, 22 June 2010 - 09:15 .

[Gray-Wolf]

Here I am with my 'big brush strokes' again but what if you alter one of the existing parameters to the point that the system accrues energy on top of it's normal 'cyclical' behaviour? (i.e. you plug up the hole in the bucket a little).

If we are setting in motion such a situation then a lot of the heat that is extra to the system may well take a long time to re-surface (some deep sea currents have over 100yr journeys before re-surfacing) and ,due to differing lengths of transit in the various deep sea currents, would 'feather 'into the system when the slightly warmer waters re-surface at cold bottom water upwelling points.

The ozone hole and it's impacts on the Antarctic circumpolar current has meant a faster overturning of the ocean currents there (with a little help from the Coriolis effect) so may well be speeding up the process (as shown by the failure of the CO2 sinks there) and seems to tie in with the acceleration in the rate of warming over the past 30yrs (whilst cooling the inner continent via it's impact on Strat temps???).

If we are indeed entering the 'zone' where past accrued heat is re-surfacing then no amount of looking to other 'drivers' will halt the warming trend and ,in fact, things are only set to get worse with both past warmth re-surfacing and Arctic Dark water accelerating/augmenting the oceans ability to absorb energy (positive feedbacks and old warming both impacting the system).

[Boar Wrinklestorm]

Gray-Wolf, on 22 June 2010 - 10:28 , said:

If we are indeed entering the 'zone' where past accrued heat is re-surfacing then no amount of looking to other 'drivers' will halt the warming trend and ,in fact, things are only set to get worse with both past warmth re-surfacing and Arctic Dark water accelerating/augmenting the oceans ability to absorb energy (positive feedbacks and old warming both impacting the system).

That is the conclusion of the LI hypothesis. It is a bleak prospect, with my own 'off-the-cuff' figures suggesting that we are at least three sunspot cycles away from any chance of seeing a cooling trend.

I think it was our Canadian cousin, Roger, that proposed a test that if the world continued to warm, even in this solar minima, then that would be possible evidence in favour of the LI as oppose to AGW. The idea is, put simply, that since the AGW signal is small but cumulative over time fluctuations in solar activity should still be visible in the temperature record. ie when the sun is less active we should see an appropriate drop in the temperature.

The LI hypothesis presupposes continuing warming since the amount of energy in the system has still to be 'leaked'. Therefore, a conlusion might be reached such that if we don't see a drop in temperature (we haven't) then that favours either the LI hypothesis, or that the AGW signal has ammassed so much, now, that it masks solar activity.

Edited by VillagePlank, 22 June 2010 - 10:49 .

[Gray-Wolf]

Thanks V.P. , either way we need to be looking at mitigating the impacts on the planets population and not quibbling over whether it is or it isn't!

I think we both feel that, like getting an oil tanker moving, the initial energy is spent on getting the momentum going. Once 'going' it takes a lot to stop that momentum.

If the last 100yrs or so have been this initial phase of 'slow build' ,and the recent acceleration in ice loss shows us now 'in motion', then we have to be aware that we are gunning the engines even more than through that initial phase and that a lot of that energy will now go straight into the process of 'change' as it is no longer needed to get things in motion (once the old perennial is gone then the energy that was used to melt it now is redundant in that role and will find another way of 'impacting' the globe).

I believe that we are in the 'crux' period of 20yrs or so of 'unexpected' change (not 'unpredicted change') with things occuring faster than we supposed that they would (as our models used 'real data' which hid the energy that was being used to set things in motion).

Now that we are 'in motion' that energy is free to augment the changes (as we see across the Arctic with everything 'ahead of times') and accelerate the pace of change and positive feedbacks.

[Yorkshiresnows]

VillagePlank, on 22 June 2010 - 10:42 , said:

That is the conclusion of the LI hypothesis. It is a bleak prospect, with my own 'off-the-cuff' figures suggesting that we are at least three sunspot cycles away from any chance of seeing a cooling trend.

I think it was our Canadian cousin, Roger, that proposed a test that if the world continued to warm, even in this solar minima, then that would be possible evidence in favour of the LI as oppose to AGW. The idea is, put simply, that since the AGW signal is small but cumulative over time fluctuations in solar activity should still be visible in the temperature record. ie when the sun is less active we should see an appropriate drop in the temperature.

The LI hypothesis presupposes continuing warming since the amount of energy in the system has still to be 'leaked'. Therefore, a conlusion might be reached such that if we don't see a drop in temperature (we haven't) then that favours either the LI hypothesis, or that the AGW signal has ammassed so much, now, that it masks solar activity.

Hi All

I think your jumping the gun a little. The Solar minimums impacts are yet to be felt in my view. We are also in process of changing over the PDO cycle.

There has been no overall warming for the past 10 years (this year has still 6 months to play, with the predicted temp spike due to El Nino about to fade) with La Nina conditions set to take hold in the next few months.

I see over on Accuweather that Joe laminate floori is looking at a drop in global temps next year, so we'll need to wait a while longer yet prior to any concluisons in my view.

Y.S

[Gray-Wolf]

Woah there trigger!!!

This is what I'm saying Y.S. , we will either see the 'predictable' run of cycles we have 'nailed' or we won't. If AGW (or whatever) has driven global temps for the past 100yrs and more then we have a lot of energy both in the system (deep sea current modification) or about to be freed to work 'with' the systems (perennial ice now 'gone' so the energy to melt now freed up to 'warm' instead). This amount of energy cannot go un -missed and be it a swamping of the PDO-ve (what are we at this month in our 'deep minimum'?) or an intensification of the AO -ve (and it's knock on impacts across the lower latitudes) we will notice it.

There will come a point that we all agree that the only way to see the changes we witness is that there is more energy within the global climate model (not less!) and the debate will be about 'how' that energy got there (I'm with mainstream science on that score!!!).

[Solar Cycles]

Yorkshiresnows, on 22 June 2010 - 12:18 , said:

Hi All

I think your jumping the gun a little. The Solar minimums impacts are yet to be felt in my view. We are also in process of changing over the PDO cycle.

There has been no overall warming for the past 10 years (this year has still 6 months to play, with the predicted temp spike due to El Nino about to fade) with La Nina conditions set to take hold in the next few months.

I see over on Accuweather that Joe laminate floori is looking at a drop in global temps next year, so we'll need to wait a while longer yet prior to any concluisons in my view.

Y.S

I'm with you on this one YS, until the PDO as switched over fully, then we will continue to see static temperatures. Though I would say it would take more than 12 months, for it to impact global temps. Fascinating times ahead in my opinion!

[kold weather]

Gray-Wolf, on 22 June 2010 - 11:58 , said:

I believe that we are in the 'crux' period of 20yrs or so of 'unexpected' change (not 'unpredicted change') with things occuring faster than we supposed that they would (as our models used 'real data' which hid the energy that was being used to set things in motion).

I think it shows just how poor some of our understanding has been that its been unexpected in some corners. Of course we were going to warm from say the late 80s and into the 1990s because the PDO/AMO both were positive and when you have that combo will have big warmings, of course not helped by the AGW in the background either.

The reason the global temps held steady in much of the 00s is simply because we held a broadly +PDO/AMO signal overall (I truely believe we didn't flip -PDO till 07 and the El Nino last winter probably will be a blip.) I think the proof that we were in a boradly was the fact we had no less than 3 El ninos in 6 years during the so called -PDO and I just don't think that sits right, esp when two were pretty decent strength as well. I think the long La Nina injected a flase signal in the PDO suggesting it was going negative when infact that was the first sign the +PDO signal was on its way out...BUT it was NOT the actual flip itself.

Where I do agree probably with you is I don't think we will go as cold as the signals would suggest once we do flip both signals. We can quite obviously still go below average, the *ONLY* time we have had a dual -PDO/AMO for even 6 months was in the end of 08 and the first 4 months of 09...and its not a shock that global temps went right back down to average...and no its not the La Nina because it was very weak indeed that winter, in fact it was technically neutral for the winter...

IF the PDO still hasn't gone negative for the most part by 2020, then I think things become interesting and we are walking in new territory...If I was to make a very long call, I think we may see a big cooling in the 20s compared to what we've seen in the last 15 years globally, next solar min will arrive right at the same time as the -ve AMO is set to start to develop, plus the PDO should be strongly negative by then. Put the three of those signals together, and if you can't get decently below average, then things are looking bad.

[jethro]

A new survey of 14 of the world's leading climate scientists (no clues as to who they were) shows that clouds are THE biggest uncertainty in the climate change debate. How they behave and the impact they have upon climate, whether positive or negative feedback is the largest problem to overcome in order to gain any degree of certainty over future temperatures.

http://green.blogs.n...est-scientists/
http://www.pnas.org/...6/24/0908906107

"The single biggest uncertainty identified by the 14 experts — and it was a unanimous judgment — was the role of clouds in the earth’s future climate."

[Gray-Wolf]

It appears to me that whatever clouds 'do' within the process of warming we will warm to the level that this amount of CO2 in the atmosphere facilitates.

Will cloud cover play a role in the 'speed' of the warming? I'm sure they will play exactly the same role they have when CO2 levels were increasing during past warmings. We may not have proxies for cloud cover but we do for what temps did........