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Dukasaur wrote:No, the facts are undeniable enough. The planet is heating up fast. The amount of CO2 in the atmosphere is likewise increasing fast. Forests are disappearing. Etc., etc. These things are measurable facts.
reconstruction of the past 5 million years of climate history, based on oxygen isotope fractionation (serving as a proxy for the total global mass of glacial ice sheets). See the discussion below for a summary of the methods and models used. Note that in 2010, User:SeL media switched the orientation of the time axis and the vertical axes, apparently without discussion, and some descriptions of the image may refer to the older version, resulting in confusion of 'right' and 'left' in the image.
Global Warming is .. ' Settled Science".. isn't it. ?
Trust me, I'm a former physics major, I studied relativity.
How do we know that changes in the Sun arenāt to blame for current global warming trends?
Since 1978, a series of satellite instruments have measured the energy output of the Sun directly. The satellite data show a very slight drop in solar irradiance (which is a measure of the amount of energy the Sun gives off) over this time period. So the Sun doesn't appear to be responsible for the warming trend observed over the past several decades.
tzor wrote:I'm going to highlight something because it's a perfect example of when you drift from the realm of "facts."Dukasaur wrote:No, the facts are undeniable enough. The planet is heating up fast. The amount of CO2 in the atmosphere is likewise increasing fast. Forests are disappearing. Etc., etc. These things are measurable facts.
The planet is heating up is a "fact."
The notion that the rate is high ("fast") is an opinion.
Trust me, I'm a former physics major, I studied relativity.
In fact the last time the CO2 rate was this high was 4 million years ago, before man. So about that temperature thing ...reconstruction of the past 5 million years of climate history, based on oxygen isotope fractionation (serving as a proxy for the total global mass of glacial ice sheets). See the discussion below for a summary of the methods and models used. Note that in 2010, User:SeL media switched the orientation of the time axis and the vertical axes, apparently without discussion, and some descriptions of the image may refer to the older version, resulting in confusion of 'right' and 'left' in the image.
Wait, what? We're like freezing compared to what was then. If you base everything on CO2 then we are already underwater but we are not. Temperatures are well below what they were 4 million years ago ...
Now we get to an interesting fact you mention ... "Forests are disappearing." But here the problem is man cutting down the forest, not as a direct cause of climate change. In Africa, wood is still used for fuel; bad to the trees but I don't think comparable to the coal based emissions from China.
So back to the measurable facts. Facts are meaningless unless put into context. Unfortunately, at this time, context is often assumed from personal bias.
P.S. CO2 and trees are not really all that they make themselves to be; breathe in and breathe out. CO2 absorption from algae might prove to be the key element in the long term. In fact, we might have more personal algae scrubbers on our rooftops than solar panels in a couple of decades. Hmmmm ... bio-diesel.
jusplay4fun wrote:Since I too am a former Physics major, does that mean my opinion is also equally valid and relative?
Scientists believe the cooling from sulfates and other reflective aerosols overwhelms the warming effect of black carbon and other absorbing aerosols over the planet. Models estimate that aerosols have had a cooling effect that has counteracted about half of the warming caused by the build-up of greenhouse gases since the 1880s. However, unlike many greenhouse gases, aerosols are not distributed evenly around the planet, so their impacts are most strongly felt on a regional scale.
The fact that our planet is getting warmer even though aerosols are cooling it down at higher rates than previously thought brings us to a Catch-22 situation: Global efforts to improve air quality by developing cleaner fuels and burning less coal could end up harming our planet by reducing the number of aerosols in the atmosphere, and by doing so, diminishing aerosols' cooling ability to offset global warming.
According to Rosenfeld, another hypothesis to explain why Earth is getting warmer even though aerosols have been cooling it down at an even a greater rate is a possible warming effect of aerosols when they lodge in deep clouds, meaning those 10 kilometers or more above the Earth. Israel's Space Agency and France's National Centre for Space Studies (CNES) have teamed up to develop new satellites that will be able to investigate this deep cloud phenomenon, with Professor Rosenfeld as its principal investigator.
Either way, the conclusion is the same. Our current global climate predictions do not correctly take into account the significant effects of aerosols on clouds on Earth's overall energy balance. Further, Rosenfeld's recalculations mean fellow scientists will have to rethink their global warming predictions -- which currently predict a 1.5 to 4.5-degree Celsius temperature increase by the end of the 21st century -- to provide us a more accurate diagnosis -- and prognosis -- of the Earth's climate.
tzor wrote:jusplay4fun wrote:Since I too am a former Physics major, does that mean my opinion is also equally valid and relative?
No, but hopefully you should know the difference between a "fact" and an "opinion" and "fast" isn't a "fact."
Here is the problem; humans do a lot of shit all the time. The environmental shit we have done in the past few decades to atone for the shit we did in the previous century could equally be the cause of temperature variations in the relatively short term interval of decades. And since we are citing NASA these days (even though they have gone PC crazy and I'm skeptical of anything post George M Lowe but whatever)
Aerosols and Incoming Sunlight (Direct Effects)
NomadPatriot wrote:so is outer space in general all the same temperature..? say universe wide..?
tzor wrote:NomadPatriot wrote:so is outer space in general all the same temperature..? say universe wide..?
First of all, the Solar "wind" caused by the ejection of gasses from the Sun goes out beyond the orbits of the known planets (Voyager five years ago passed the boundary) and effectively the interstellar medium is pushed away by it. The distance is around 121 AU.
Never the less, there is only two ideas of temperature especially as it related to transfer of temperature. There are two means radiation and conduction. Unless you are really hot, it takes a long while to radiate your heat. Likewise the thinness of space makes it hard to conduct heat to an adjacent body.
So both in terms of conduction and convection, the sun has the greatest influence. Conduction gets complicated because of the effect of the magnetosphere pushing away the wind in the same way the solar wind pushes away the interstellar wind.
Currently we pass though spiral arms in the galaxy every 100 million years and spend about 10% of that time in the arm. We are currently in the Orion spur. That's generally beyond the normal calculations of weather patterns.
jusplay4fun wrote:Discussion of solar wind in this context is complete obfuscation.
tzor wrote:jusplay4fun wrote:Discussion of solar wind in this context is complete obfuscation.
I know, but it's fun obfuscation.
riskllama wrote:
riskllama wrote:lol, NP must've missed the Jessica Hahn cameo...*shrugs*
riskllama wrote:global warming?
jonesthecurl wrote:Well, to be fair, Tzor was just replying to NoPoint's ridiculous "maybe it's space that's getting warmer" idea.
jusplay4fun wrote:Take the forecast for hurricane Dorian; we do not know exactly where it will go, but we can describe very probable paths for its motion.
the mathematician Hari Seldon spends his life developing a theory of psychohistory, a new and effective mathematical sociology. Using statistical laws of mass action, it can predict the future of large populations.
Weather is chaotic but climate is driven by Earth's energy imbalance, which is more predictable.
One of the defining traits of a chaotic system is 'sensitive dependence to initial conditions'. This means that even very small changes in the state of the system can quickly and radically change the way that the system develops over time. Edward Lorenz's landmark 1963 paper demonstrated this behavior in a simulation of fluid turbulence, and ended hopes for long-term weather forecasting.
However, climate is not weather, and modeling is not forecasting.
Although it is generally not possible to predict a specific future state of a chaotic system (there is no telling what temperature it will be in Oregon on December 21 2012), it is still possible to make statistical claims about the behavior of the system as a whole (it is very likely that Oregon's December 2012 temperatures will be colder than its July 2012 temperatures). There are chaotic components to the climate system, such as El Nino and fluid turbulence, but they all have much less long-term influence than the greenhouse effect. It's a little like an airplane flying through stormy weather: It may be buffeted around from moment to moment, but it can still move from one airport to another.
Nor do climate models generally produce weather forecasts. Models often run a simulation multiple times with different starting conditions, and the ensemble of results are examined for common properties. This is, incidentally, a technique used by mathematicians to study the Lorenz functions.
The chaotic nature of turbulence is no real obstacle to climate modeling, and it does not negate the existence or attribution of climate change.
tzor wrote:jusplay4fun wrote:Take the forecast for hurricane Dorian; we do not know exactly where it will go, but we can describe very probable paths for its motion.
That's because the direction a hurricane goes is mostly dependent on the major air masses around it (as well as ocean/land conditions) , something that can be roughly modeled to an extent.
The problem is that the major factors to climate in general are not known to that degree, which is why most if not all models on long term climate generate completely inaccurate predictions. In addition, the time scale of climate change is go much longer that those minor factors start to play significant roles.
Here is the problem; humans do a lot of shit all the time. The environmental shit we have done in the past few decades to atone for the shit we did in the previous century could equally be the cause of temperature variations in the relatively short term interval of decades. And since we are citing NASA these days (even though they have gone PC crazy and I'm skeptical of anything post George M Lowe but whatever)
The current warming trend is of particular significance because most of it is extremely likely (greater than 95 percent probability) to be the result of human activity since the mid-20th century and proceeding at a rate that is unprecedented over decades to millennia.
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