Major Snows Not due to AGW

[WeatherRusty]

Uhhh, la nina cools the global temperature...yet global precip increases. Don't isolate the pacific.

The global temperature is an average. There are plenty of above normal temps around the world during La Nina.

[tacoman25]

The warming of the global oceans is not supposed to cause a large enough increase in precipitation to be detectable with our current inadequate observation network.

If that is the case, then we really don't need to worry about it causing significantly greater storms/snowfall/etc.

Al Gore was reaching, as usual.

[BethesdaWX]

The global temperature is an average. There are plenty of above normal temps around the world during La Nina.

Yes...average precip should drop...It doesn't

Global Precip has been higher in cooler time periods...PDO...etc

Global precip has been dropping for 35 years

http://www.waterency...ogic-Cycle.html

[skierinvermont]

Not true

I want some evidence, give a me a link from the IPCC saying this...anyone.

ENSO does it, PDO does it...A "massive global sea level warming" would do this as well, the ocean holds so much energy, the water cycle would have to gain momentum.

http://www.waterency...ogic-Cycle.html

Skier...learn

The predicted change in global precipitation is an increase of 4-5% globally. Assuming the response is linear, and we have only experienced .8C of warming thus far, that would mean a mere 1% increase over the last century.

So we are talking about a mere 1% increase in precipitation globally.. which is far too small to detect with out current observation network.

I also suspect that the response is non-linear given the oceans have warmed only half what the land has which has probably led to lower humidities and less precipitation than if the response were more equal - which over time it is expected to be (though not completely equal).

[WeatherRusty]

Yes...average precip should drop...It doesn't

Global Precip has been higher in cooler time periods...PDO...etc

Global precip has been dropping for 35 years

http://www.waterency...ogic-Cycle.html

Are you sure you intended to link the site above. It reads like I wrote it, and makes every single point I have made in my posts found in this thread!

[skierinvermont]

And after you found out there was no increasing trend. And we all suspected that there was supposed to be more precip, that would seem to make sense with more water vapor.

I honestly didn't know which to expect.. I probably would have guessed slight increase. However, this had nothing to do with my conclusion that the data is inaccurate and imprecise. As I have explained, there are very basic obvious mathematical and practical reasons for why the data is inaccurate and imprecise. Which it seems you have agreed to.

I asserted this both before and after I knew what the actual theoretical expectation was.

[BethesdaWX]

Are you sure you intended to link the site above. It reads like I wrote it, and makes every single point I have made in my posts found in this thread!

It states my point.....Warming of the Oceans overall to the extent we have seen should have produced a significant increase in Global Precipitation.

Why is Global Precipitation HIGHER in cold PDOs (global cooling), and LOWER in warm periods?

[skierinvermont]

Are you sure you intended to link the site above. It reads like I wrote it, and makes every single point I have made in my posts found in this thread!

Indeed. It seems to agree with exactly what we have been saying. "The global hydrological cycle has intensified."

It brings up a couple interesting points, for example the United States has experienced increased precipitation which is interesting because it is one of the places expected to receive more precip (In the northern and eastern U.S., the southwest dries) and it is one of the few regions we have decent data for.

[salbers]

I would note the precipitation should match evaporation globally. Evaporation in turn is driven largely by solar energy - something that is relatively constant.

[BethesdaWX]

The predicted change in global precipitation is an increase of 4-5% globally. Assuming the response is linear, and we have only experienced .8C of warming thus far, that would mean a mere 1% increase over the last century.

So we are talking about a mere 1% increase in precipitation globally.. which is far too small to detect with out current observation network.

I also suspect that the response is non-linear given the oceans have warmed only half what the land has which has probably led to lower humidities and less precipitation than if the response were more equal - which over time it is expected to be (though not completely equal).

LINK??? Atmospheric Warming is not the Same as Ocean Warming...the atmosphere holds lole 0.00001% of the water on this planet, and holds a fraction of the energy...if the OCEANS have warmed as much as we claimed they have...the increase in global precip would be SIGNIFICANT.....and certainly would not be DROPPING for 35 YEARS during the Warmest Decades ever.

This is the whole point here, If we cannot even accurately predict the Water Vapor/Global Precipitation realtionship, how can we accurately predict how Solar/IR, GCC, CO2, GCR, MagF decrease, Deep Ocean Currents, etc, impact the our atmosphere & then the global temp? Co2/Atmosphere/energy storage is alot more complicated than Water Vapor/Global precip

Stratospheric warming has not occured how we expected it to do so either! If Co2 energy forxing cannot affect the stratosphere to a high extent,how can we expect it to do so to the Oceans? The energy budget we have assumed is that CO2 is more dominant than it really is.....we've screwed up.

[skierinvermont]

LINK??? Atmospheric Warming is not the Same as Ocean Warming...the atmosphere holds lole 0.00001% of the water on this planet, and holds a fraction of the energy...if the OCEANS have warmed as much as we claimed they have...the increase in global precip would be SIGNIFICANT.....and certainly would not be DROPPING for 35 YEARS during the Warmest Decades ever.

This is the whole point here, If we cannot even accurately predict the Water Vapor/Global Precipitation realtionship, how can we accurately predict how Solar/IR, GCC, CO2, GCR, MagF decrease, Deep Ocean Currents, etc, impact the our atmosphere & then the global temp? Co2/Atmosphere/energy storage is alot more complicated than Water Vapor/Global precip

Stratospheric warming has not occured how we expected it to do so either! If Co2 energy forxing cannot affect the stratosphere to a high extent,how can we expect it to do so to the Oceans? The energy budget we have assumed is that CO2 is more dominant than it really is.....we've screwed up.

The warming of SSTs so far would only be enough to produce about a 1% increase in global precipitation, which is too small of a change to detect with our current observational network.

The 1% figure is an AT MOST figure and is based off the fact that the much larger level of warming anticipated by 2100 is only supposed to produce a 4% increase in land precipitation. This 4% figure can be found in the IPCC report.

[tacoman25]

The predicted change in global precipitation is an increase of 4-5% globally. Assuming the response is linear, and we have only experienced .8C of warming thus far, that would mean a mere 1% increase over the last century.

So we are talking about a mere 1% increase in precipitation globally.. which is far too small to detect with out current observation network.

I also suspect that the response is non-linear given the oceans have warmed only half what the land has which has probably led to lower humidities and less precipitation than if the response were more equal - which over time it is expected to be (though not completely equal).

I still don't see any evidence that would indicate warmer ocean temps result in more global precipitation. You keep dismissing the ENSO connection, not sure why. If the general principal is the same, El Ninos should produce more precip than La Ninas, and they clearly don't.

[BethesdaWX]

The warming of SSTs so far would only be enough to produce about a 1% increase in global precipitation, which is too small of a change to detect with our current observational network.

The 1% figure is an AT MOST figure and is based off the fact that the much larger level of warming anticipated by 2100 is only supposed to produce a 4% increase in land precipitation.

Bull****, The oceans warming at the amount the supposedly have would do alot more.

L....I.....N....K

Heres Mine

http://www.waterencyclopedia.com/Ge-Hy/Global-Warming-and-the-Hydrologic-Cycle.html

[skierinvermont]

Bull****, The oceans warming at the amount the supposedly have would do alot more.

L....I.....N....K

Heres Mine

http://www.waterency...ogic-Cycle.html

Please quote the part where it says a .5C increase in global SSTs would produce more than a 1% increase in global precipitation.

Here is my quote from IPCC Ch10 p 768:

"Overall precipitaiton over land increases by about 5% while precipitation over ocean increases by about 4%"

These are predictions by 2100. Obviously the predicted magnitude of change by 2100 is much greater than the magnitude of change by 2010. Therefore I concluded that if the response were linear (which it probably isn't) global precipitation should have increased 1% over the last century.

This is too small of a change to detect with our current observational network.

[skierinvermont]

I still don't see any evidence that would indicate warmer ocean temps result in more global precipitation. You keep dismissing the ENSO connection, not sure why. If the general principal is the same, El Ninos should produce more precip than La Ninas, and they clearly don't.

It's actually quite basic.. over extended periods the amount of water entering the ocean and land must balance the water leaving the ocean and land (minus any change in water vapor). If the oceans are warmer, do you deny that there would be more evaporation?

Unless precipitation also increases then we would witness a constant and very rapid build up of water vapor in the atmosphere.

We can also look at the paleo record and see that during times of great warmth, the earth was much wetter.

During El Ninos we witness a decline in precipitation but a large increase in water vapor. During La Ninas we witness a decrease in water vapor but an increase in precipitation. The same principles are not at work because ENSO is a sharp abrupt fluctuation in global weather patterns while climate change is a general warming of the global oceans and atmosphere.

[WeatherRusty]

It's actually quite basic.. over extended periods the amount of water entering the ocean and land must balance the water leaving the ocean and land (minus any change in water vapor). If the oceans are warmer, do you deny that there would be more evaporation?

Unless precipitation also increases then we would witness a constant and very rapid build up of water vapor in the atmosphere.

We can also look at the paleo record and see that during times of great warmth, the earth was much wetter.

During El Ninos we witness a decline in precipitation but a large increase in water vapor. During La Ninas we witness a decrease in water vapor but an increase in precipitation. The same principles are not at work because ENSO is a sharp abrupt fluctuation in global weather patterns while climate change is a general warming of the global oceans and atmosphere.

And as mentioned within Bethesda's recent link, increased dust shows up in ice cores representing the last full glaciation. This implies that when it is colder the atmosphere is drier (less precip). and dustier.

[BethesdaWX]

Please quote the part where it says a .5C increase in global SSTs would produce more than a 1% increase in global precipitation.

Here is my quote from IPCC Ch10 p 768:

"Overall precipitaiton over land increases by about 5% while precipitation over ocean increases by about 4%"

These are predictions by 2100. Obviously the predicted magnitude of change by 2100 is much greater than the magnitude of change by 2010. Therefore I concluded that if the response were linear (which it probably isn't) global precipitation should have increased 1% over the last century.

This is too small of a change to detect with our current observational network.

If you ask me, precip increase should be logorithmic.....where is the quote saying the past century should have risen by 1%? No one has said that but you.

Even so, Precip has been dropping for 35yrs.

Now, what is your thought o.......... AGW "causing harsher blizzards".............? I hope you know that NH snowcover has not changed at all since 1950, there has been no decrease. Snowstorm patterns follow the NAO/AO,not global temps.

Do you accept this fact?

[salbers]

It's actually quite basic.. over extended periods the amount of water entering the ocean and land must balance the water leaving the ocean and land (minus any change in water vapor). If the oceans are warmer, do you deny that there would be more evaporation?

Unless precipitation also increases then we would witness a constant and very rapid build up of water vapor in the atmosphere.

We can also look at the paleo record and see that during times of great warmth, the earth was much wetter.

During El Ninos we witness a decline in precipitation but a large increase in water vapor. During La Ninas we witness a decrease in water vapor but an increase in precipitation. The same principles are not at work because ENSO is a sharp abrupt fluctuation in global weather patterns while climate change is a general warming of the global oceans and atmosphere.

I still like to look at the role of solar radiation reaching the ground relating to latent heat release and thus controlling the hydrologic cycle. This is a bit distinct from simply looking at the temperature.

http://iopscience.io...9326/5/2/025203

[Isotherm]

Here's an idea regarding the El Nino/La Nina precip pattern:

1. El Nino generally involves a weakening of the mid latitude jet and strengthening of the sub-tropical jet.

2. Thus precipitation anomalies during an El Nino event should average higher in the tropics/sub-tropics (and into the southern US).

3. La Nina generally involves the inverse pattern - an energizing of the mid latitude jet and weakening of the sub tropical jet.

4. Thus precipitation anomalies during a La Nina episode should average higher in the mid-latitudes.

5. Global landmass is quite a bit higher in the northern hemisphere's mid-latitudes compared to the sub-tropics and tropics.

6. Since precipitation anomaly obervations are taken at land stations, (in addition, the Southern Hemisphere has much less geographic coverage of land than the northern hemisphere) it's probable that La Nina events average wetter than El Nino's.

I'd expect precipitation to be higher within the 30S to 30N latitude range during El Nino's, and there could very well be more global precipitation during el ninos (we just can't record it). However, since La Nina's energize the mid latitude jet, more precipitation is falling from 30N to 60N where more land obervations stations are located.

[salbers]

Does TRMM show anything for this, as it's been designed to measure tropical precipitation?

[tacoman25]

It's actually quite basic.. over extended periods the amount of water entering the ocean and land must balance the water leaving the ocean and land (minus any change in water vapor). If the oceans are warmer, do you deny that there would be more evaporation?

Unless precipitation also increases then we would witness a constant and very rapid build up of water vapor in the atmosphere.

We can also look at the paleo record and see that during times of great warmth, the earth was much wetter.

During El Ninos we witness a decline in precipitation but a large increase in water vapor. During La Ninas we witness a decrease in water vapor but an increase in precipitation. The same principles are not at work because ENSO is a sharp abrupt fluctuation in global weather patterns while climate change is a general warming of the global oceans and atmosphere.

So the water cycle waits years to complete while going from Nino to Nina? And you still offer no explanation for why precip increases with La Nina cooling.

[tacoman25]

Here's an idea regarding the El Nino/La Nina precip pattern:

1. El Nino generally involves a weakening of the mid latitude jet and strengthening of the sub-tropical jet.

2. Thus precipitation anomalies during an El Nino event should average higher in the tropics/sub-tropics (and into the southern US).

3. La Nina generally involves the inverse pattern - an energizing of the mid latitude jet and weakening of the sub tropical jet.

4. Thus precipitation anomalies during a La Nina episode should average higher in the mid-latitudes.

5. Global landmass is quite a bit higher in the northern hemisphere's mid-latitudes compared to the sub-tropics and tropics.

6. Since precipitation anomaly obervations are taken at land stations, (in addition, the Southern Hemisphere has much less geographic coverage of land than the northern hemisphere) it's probable that La Nina events average wetter than El Nino's.

I'd expect precipitation to be higher within the 30S to 30N latitude range during El Nino's, and there could very well be more global precipitation during el ninos (we just can't record it). However, since La Nina's energize the mid latitude jet, more precipitation is falling from 30N to 60N where more land obervations stations are located.

This sounds like a reasonable guess. I guess we'd need to see La Nina/El Nino precip patterns throughout the world to back that up.

[skierinvermont]

So the water cycle waits years to complete while going from Nino to Nina? And you still offer no explanation for why precip increases with La Nina cooling.

Yes I did.. I said that ENSO is a an abrupt alteration of global weather patterns and that this alteration may cause short term changes in precipitation which is the same thing that Isotherm is asserting and which you just sounds reasonable.

It also may be directly related to the global cooling. You have suggested that the same mechanism that would cause more precip in a warmer world should cause more precip in a Nino which warms the earth.

However, there is a difference between simply being warmer, and rapidly warming. A warm world in a warm base state is not the same thing as a rapidly warming world. It's a different mechanism.

A warm world has more water vapor, more evaporation and more precipitation. If such a warm world were to experience a sudden cooling (say due to a Nina) the atmosphere would rapidly cool and it would no longer hold as much water. I think this is why I have heard Ninas described as acting like a sponge on the water cycle... it rings the water out. Now if the world were to stay at this new cold temperature, then eventually all the water would get rung out and precipitation would actually decrease to lower levels than they were originally.

During Ninos we see rapid spikes in water vapor, but drops in precip. So what is probably happening is the atmosphere has warmed faster than the hydrologic cycle can keep up. Water vapor increases rapidly but humidities are still lower because the atmosphere is so much warmer. If we were to stay in an El Nino for a long time.. eventually WV would rise to a new equilibrium and precipitation would eventually catch up.

So basically, short term 1-yr sharp fluctuations in temperature would have a different effect than the earth gradually transitioning to a warmer base state.

[tacoman25]

Yes I did.. I said that ENSO is a an abrupt alteration of global weather patterns and that this alteration may cause short term changes in precipitation which is the same thing that Isotherm is asserting and which you just sounds reasonable.

It also may be directly related to the global cooling. You have suggested that the same mechanism that would cause more precip in a warmer world should cause more precip in a Nino which warms the earth.

However, there is a difference between simply being warmer, and rapidly warming. A warm world in a warm base state is not the same thing as a rapidly warming world. It's a different mechanism.

A warm world has more water vapor, more evaporation and more precipitation. If such a warm world were to experience a sudden cooling (say due to a Nina) the atmosphere would rapidly cool and it would no longer hold as much water. I think this is why I have heard Ninas described as acting like a sponge on the water cycle... it rings the water out. Now if the world were to stay at this new cold temperature, then eventually all the water would get rung out and precipitation would actually decrease to lower levels than they were originally.

During Ninos we see rapid spikes in water vapor, but drops in precip. So what is probably happening is the atmosphere has warmed faster than the hydrologic cycle can keep up. Water vapor increases rapidly but humidities are still lower because the atmosphere is so much warmer. If we were to stay in an El Nino for a long time.. eventually WV would rise to a new equilibrium and precipitation would eventually catch up.

So basically, short term 1-yr sharp fluctuations in temperature would have a different effect than the earth gradually transitioning to a warmer base state.

I see what you are saying...but if that were the case, La Ninas today should be causing more precip than Ninas in the 1950s, 1960s, and 1970s. I have not seen any meaningful evidence of that, so getting back to the original point: anyone like Gore who is claiming that AGW is responsible for more monster storms and blizzards has no factual basis for those claims.

It's just another scare-mongering tactic of blaming any kind of "extreme" on AGW.

[skierinvermont]

I see what you are saying...but if that were the case, La Ninas today should be causing more precip than Ninas in the 1950s, 1960s, and 1970s. I have not seen any meaningful evidence of that, so getting back to the original point: anyone like Gore who is claiming that AGW is responsible for more monster storms and blizzards has no factual basis for those claims.

It's just another scare-mongering tactic of blaming any kind of "extreme" on AGW.

Except the underlying trend from the 1950s is too small to detect and could easily be overwhelmed by other factors. Whereas the effect of ENSO, which is a different mechanism, is much larger and faster and so is detectable.

[BethesdaWX]

Except the underlying trend from the 1950s is too small to detect and could easily be overwhelmed by other factors. Whereas the effect of ENSO, which is a different mechanism, is much larger and faster and so is detectable.

The trend has been decreasing precip for almost 40yrs... Several Deviations actually

[skierinvermont]

The trend has been decreasing precip for almost 40yrs... Several Deviations actually

And as I've pointed out the error bars and descrepancies between multiple sources are so large it is not statistically significantly different from zero. Moreover, such a weak underlying trend could easily be overridden by other factors.

[tacoman25]

Except the underlying trend from the 1950s is too small to detect and could easily be overwhelmed by other factors. Whereas the effect of ENSO, which is a different mechanism, is much larger and faster and so is detectable.

Could be. But like I said, there is certainly no conclusive evidence. The data we do have, questionable as it may be, shows nothing supporting these claims.

[BethesdaWX]

And as I've pointed out the error bars and descrepancies between multiple sources are so large it is not statistically significantly different from zero. Moreover, such a weak underlying trend could easily be overridden by other factors.

You don't need to go into denial over possible errors. Where we measure, precip has been declining. What underlying trends have supported less precip? The Sun/Solar Max. Would Less Precip imply less GCC? Maybe. Since we do not have any good ways to measure GCC, we cannot tell exactly what has been going on.

Over 2 standard deviations of downward trending precip while temps warm during the same timeframe...40 years of steady "drying" of 2 standard deviations is significant in what we can expect from precip trends.

As both you and I discussed earlier...the IPCC projections of warming would only create 5% increase in global precipitations......BUT.....what are we comparing this "percentage" to? Total global mean precip?

More importantly, "standard deviations" on the graph I posted may be less significant than the "standard table" in Percentages derived from avg GP. Really, you need to read into this a bit more.