Every 1500 years new warming

[DogmaHunter]

All of the warming trends that have gone before have ended. So why not this one.

Because this time around, the level of CO2, a greenhouse gas, is more then DOUBLE the max level it has been at in the past 650.000 years.

And this doubling isn't the result of natural processes. It's not the result of volcano's as some have hilariously tried to claim. It is 100% the result of human activity.

For a frame of reference, the last major eruption of mount st helens in the 80's, has pumped an equivalent of CO2 in the air as ONE HOUR of human activity. ONE HOUR.

Take ALL volcanic activity around the globe for the past 300 years and it doesn't even account for a fraction of what global human activity puts out in only a month!

The Medieval warm period. The Holocene Maximum. The Roman warm period. Three others they were all 1500 years apart. They all had a end .

And none of them had to deal with a more then DOUBLING of CO2 concentrations. You know... that gas that traps heat.

 

[JackRT]

Flat no growth in temperature trend globally since 2000.

I can agree with this statement. What this says to me is that the temperature is still trending upward but not any faster. Is that what you meant to say?

 

[majj27]

Greatcloud, are you getting your information from the idea of a warming hiatus from 1998-2008? I've looked for information about what you're saying so I can give it a look-over, but that's all I can find, and I want to make certain I'm looking at the right information.

 

[AirPo]

This modern warming we are experiencing is natural and before this one there was the Medieval warm period. And before that the Holocene Maximum. And before that the Roman warm period. No coal-fired power plants no cars , just natural cycles. So why spend billions of dollars on something that is going to have about 20 years left on the cycle then back to normal.

Because all the previous warming cycles you mentioned set the baseline for what is normal. This one is not normal.

 

[AirPo]

Still you can't deny that this is one of many warming periods we have had. They all had a rapid onset too.

Not like this one, that's the point.

 

[RickG]

This modern warming we are experiencing is natural and before this one there was the Medieval warm period. And before that the Holocene Maximum. And before that the Roman warm period. No coal-fired power plants no cars , just natural cycles. So why spend billions of dollars on something that is going to have about 20 years left on the cycle then back to normal.

Because it is not a natural cycle. The Medieval warm period is a regional temp. proxy, not global temperatures. We know it is due to increased CO2 from fossil fuels. Scientists have known the effects of CO2 in the atmosphere for 150 (Fourier) years. Global Warming due to increased CO2 and the amount it would take has been documented in the scientific literature since the 1890's (Arrhenius). CO2 hasn't be as high as it is now for 3 million years (Pliocene). Even during the interglacials shown in ice cores over the past 800,000 years, the CO2 was only 280 ppm or less, presently being 409 ppm and rising at a rate of 2ppm/yr. We also know that the additional CO2 is indeed to fossil fuel CO2 by way of stable carbon isotope ratios (13C/12C) in the atmosphere . And no one has been able to show any natural forcing (cause) that can be attributed to the current warming rise. The suns TSI has declined over the past 45 years and we are in a Milankovitch Cycle that should have us cooling again.

 

[AV1611VET]

This modern warming we are experiencing is natural and before this one there was the Medieval warm period. And before that the Holocene Maximum. And before that the Roman warm period. No coal-fired power plants no cars , just natural cycles. So why spend billions of dollars on something that is going to have about 20 years left on the cycle then back to normal.

It's like I told these guys before:

Don't harp to me about anthropogenic climate change if you:

1. drive a gas-powered car
2. have a cement patio
3. have glass windows
4. have a barbecue grill
5. have a fireplace
6. drink pop
7. use a CO2 extinguisher

You guys who harp on us about using a computer to deny science: walk your own talk.

 

[Greatcloud]

Rick G the Medieval warm period was not a temperature proxy it was one in a series of warming periods we have had every 1500 years.

 

[AirPo]

Rick G the Medieval warm period was not a temperature proxy it was one in a series of warming periods we have had every 1500 years.

Which has nothing to do with the current warming cycle.

 

[JackRT]

It is my understanding that the Medieval Warm Period was limited to the North Atlantic and the land masses adjacent. It is hypothesized that it was caused by a change in the oceanic currents.

 

[majj27]

Rick G the Medieval warm period was not a temperature proxy it was one in a series of warming periods we have had every 1500 years.

Wait a tic... the Medieval Warm Period was 950 to 1250, approximately. If there was a 1500 year cycle then our next warm period is due around 2450, not 2000. Shouldn't we be at the tail end of the COOL part of the cycle right now?

 

[RickG]

Rick G the Medieval warm period was not a temperature proxy it was one in a series of warming periods we have had every 1500 years.

Thank you for your reply but I think you have a misunderstanding of what proxies are. Climate, and/or, temperature proxies are methods for determining climate conditions and temperatures prior to instrument records. Proxy sources include tree rings, boreholes, ice cores, sub-fossil pollen, corals, lake and ocean sediments and speleothems.

As for the Medieval warm period, it was unique to the northern hemisphere, not a global event. Also, through climate proxies we know the reason for the MWP, which was due to higher than average solar radiation and less volcanic activity. Neither of those factors are cyclic for the 600 year duration (800-1400 AD) of the MWP.

As for it being a 1500 year cycle, it is an incorrect argument failing to include global proxy data. When both southern and northern hemispheric proxy data are included together on a global scale there is no global 1500 year cycle, rather a hemispheric distribution variation, which is quite different from what we are seeing since the beginning of the industrial revolution.

 

[Cearbhall]

No coal-fired power plants no cars , just natural cycles. So why spend billions of dollars on something that is going to have about 20 years left on the cycle then back to normal.

Because this time we do have coal-fired power plants, cars, etc. It's not going to go back to normal.