APOD and General Astronomy Discussion Forum
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The word "Poilitcs" isn't necessary for it to be political.owlice wrote:StACase,
APOD did not mention politics. Kindly read the APOD text.
If you cannot be polite here, please do not post. Thank you.
Owlice with her Forum Admin hat on
I agree. There was no politics here, just science. The science of climatology and its study of modern anthropogenic warming is not politics, and is not particularly political (and to the extent it is, it's just the same politics found in all science, that comes from the drive to be right, the need for grants, etc).StACase wrote:And I really think that Astronomy Picture of the Day ought to leave politics alone.
http://en.wikipedia.org/wiki/The_Day_After_Tomorrow wrote:
<<The Day After Tomorrow is a 2004 American/Canadian science fiction disaster film co-written, directed, and produced by Roland Emmerich. The film was made in Toronto and Montreal and is the highest-grossing Hollywood film to be made in Canada (if adjusted for inflation).
The film depicts catastrophic effects of global warming in a series of extreme weather events that usher in global cooling and leads to a new ice age.>>
There is probably some sort of a negative feedback effect to global warming in the sense that the light fresh water input of melting Arctic Ice (both floating & non floating) tends to slow down the North Atlantic "Conveyor"/ThermoHaline Circulation (THC). This may be the primary cause of the Atlantic Multidecadal Oscillation (especially its ~60 year cycle).http://en.wikipedia.org/wiki/Younger_Dryas wrote:
<<The Younger Dryas stadial, also referred to as the Big Freeze, was a geologically brief (1,300 ± 70 years) period of cold climatic conditions and drought which occurred between approximately 12,800 and 11,500 years BP. The Younger Dryas stadial is thought to have been caused by the collapse of the North American ice sheets, although rival theories have been proposed.
The prevailing theory is that the Younger Dryas was caused by significant reduction or shutdown of the North Atlantic "Conveyor", which circulates warm tropical waters northward, in response to a sudden influx of fresh water from Lake Agassiz and deglaciation in North America. Geological evidence for such an event is thus far lacking. The global climate would then have become locked into the new state until freezing removed the fresh water "lid" from the north Atlantic Ocean. (An alternative theory suggests instead that the jet stream shifted northward in response to the changing topographic forcing of the melting North American ice sheet, bringing more rain to the North Atlantic which freshened the ocean surface enough to slow the thermohaline circulation.) There is evidence that some previous glacial terminations had post glacial cooling periods similar to the Younger Dryas.>>
http://en.wikipedia.org/wiki/Thermohaline_circulation wrote: <<ThermoHaline Circulation (THC) refers to a part of the large-scale ocean circulation that is driven by global density gradients created by surface heat and freshwater fluxes. Wind-driven surface currents (such as the Gulf Stream) travel polewards from the equatorial Atlantic Ocean, cooling en route, and eventually sinking at high latitudes (forming North Atlantic Deep Water). This dense water then flows into the ocean basins. While the bulk of it upwells in the Southern Ocean, the oldest waters (with a transit time of around 1600 years) upwell in the North Pacific. Extensive mixing therefore takes place between the ocean basins, reducing differences between them and making the Earth's oceans a global system. On their journey, the water masses transport both energy (in the form of heat) and matter (solids, dissolved substances and gases) around the globe. As such, the state of the circulation has a large impact on the climate of the Earth.
The thermohaline circulation is sometimes called the ocean conveyor belt, the great ocean conveyor, or the global conveyor belt. On occasion, it is used to refer to the meridional overturning circulation (often abbreviated as MOC). The term MOC, however, is more accurate and well defined, as it is difficult to separate the part of the circulation which is actually driven by temperature and salinity alone as opposed to other factors such as the wind and tidal forces. Temperature and salinity gradients can also lead to a circulation which does not add to the MOC itself.
The movement of surface currents pushed by the wind is fairly intuitive. For example, the wind easily produces ripples on the surface of a pond. Thus the deep ocean — devoid of wind — was assumed to be perfectly static by early oceanographers. However, modern instrumentation shows that current velocities in deep water masses can be significant (although much less than surface speeds).
In the deep ocean, the predominant driving force is differences in density, caused by salinity and temperature variations (increasing salinity and lowering the temperature of a fluid both increase its density). There is often confusion over the components of the circulation that are wind and density driven. Note that ocean currents due to tides are also significant in many places; most prominent in relatively shallow coastal areas, tidal currents can also be significant in the deep ocean.
The density of ocean water is not globally homogeneous, but varies significantly and discretely. Sharply defined boundaries exist between water masses which form at the surface, and subsequently maintain their own identity within the ocean. They position themselves one above or below each other according to their density, which depends on both temperature and salinity.
Warm seawater expands and is thus less dense than cooler seawater. Saltier water is denser than fresher water because the dissolved salts fill interstices between water molecules, resulting in more mass per unit volume. Lighter water masses float over denser ones (just as a piece of wood or ice will float on water, see buoyancy). This is known as "stable stratification". When dense water masses are first formed, they are not stably stratified. In order to take up their most stable positions, water masses of different densities must flow, providing a driving force for deep currents.>>
StACase,StACase wrote:The word "Poilitcs" isn't necessary for it to be political.owlice wrote:StACase,
APOD did not mention politics. Kindly read the APOD text.
If you cannot be polite here, please do not post. Thank you.
Owlice with her Forum Admin hat on
Scaring people is a terrible tactic, in my opinion. I mean, look where it's gotten us so far.mjimih wrote:What steps does mankind need to take to reduce the temperature of the earth one degree over the next hundred years?
That would mean changing the trend going in the opposite direction. Another 1 degrees C is already baked in (no pun intended). So back to less than where we are now by 1, is -3. That's a tall order given the current worldwide circumstances.
Immediate action. Ban the internal combustion engine. Perfect cold fusion (please!) and educate the masses on the value of preserving nature, using less resources, slowing population growth, oh and use science to legitimately scare the heck out of us into action.
geckzilla wrote:
To me all of these are indications that our population is simply too large and coming up with more and more coping mechanisms is like putting a bunch bandaids on a gaping wound. You can hope for some kind of miracle energy source like cold fusion but we have to deal with our problems now and stop the wishful thinking as if wishing makes it possible.
How dramatic.neufer wrote:
My point was that climate scientists cannot even agree on what percentage each gas has of the total greenhouse effect. They do agree that the greenhouse gas you left out, water vapor, has the greatest effect with ranges of 60% to 90% of the total greenhouse effect. It is ridiculous to try to regulate a minor greenhouse gas when no one agrees on how much of an effect it has. If global warming is caused by CO2 emissions of humans, I prefer to think of it as lessening the impact of the next ice age.mjimih wrote:I love lists like this. It's fun going thru them honestly.
Climb mate conned wrote:
What is the consensus on the cause of ice ages?
"natural" variability in Earth's weather cycles. That are caused by prevailing weather patterns. Influenced by ocean currents, massive volcano's, etc. These changes can happen rapidly. A man made influence on such weather systems at the scale needed are NOT natural.
What is the consensus on the effects of various greenhouse gasses?
They (Methane, CO2) trap heat, causing Earth to "preserve" energy it receives from the Sun. Bad if you do not have an air-conditioner.
Climate scientists fully agree on what percentage each gas has on the total greenhouse effect in each of their models.Climb mate conned wrote:
My point was that climate scientists cannot even agree on what percentage each gas has of the total greenhouse effect.
Some models do, in fact, predict a drying of the upper atmosphere due to stronger Hadley Circulation.Climb mate conned wrote:
They do agree that the greenhouse gas you left out, water vapor, has the greatest effect with ranges of 60% to 90% of the total greenhouse effect.
It is ridiculous to try avoid the next ice age when no one agrees onClimb mate conned wrote:
It is ridiculous to try to regulate a minor greenhouse gas when no one agrees on how much of an effect it has. If global warming is caused by CO2 emissions of humans, I prefer to think of it as lessening the impact of the next ice age.
I would be highly surprised if coal and oil/tar sands companies aren't already spending that sort of money to disprove AGWClimb mate conned wrote:
If I offered million dollar research grants to disprove AGW, I think we would see consensus switch.
There has been no decline over the past 130 years.Climb mate conned wrote:
I leave you with my favorite climate scientist quote: "Hide the decline!"
In fact, models agree reasonably closely in this respect. That there is much to be learned is certain. But so what? Cosmologists can't agree on values for important parameters that profoundly affect the development and evolution of the Universe. But that doesn't mean they don't broadly agree on the Big Bang cosmology. Biologists have all sorts of disputes about the parameters that influence evolution, but they all agree that evolution is happening.Climb mate conned wrote:My point was that climate scientists cannot even agree on what percentage each gas has of the total greenhouse effect.
A statement that simply reflects your vast ignorance on the subject, and effectively means we can ignore anything you have to say about climate science.They do agree that the greenhouse gas you left out, water vapor, has the greatest effect with ranges of 60% to 90% of the total greenhouse effect. It is ridiculous to try to regulate a minor greenhouse gas when no one agrees on how much of an effect it has.
http://earthobservatory.nasa.gov/IOTD/view.php?id=81736 wrote:<<The summer of 2012 was the most severe wildfire season Russia had faced in a decade. 2013 might be headed in the same direction after an unusual heat wave brought a surge of fire activity in northern Siberia in July.
A persistent high-pressure weather pattern in the Russian Arctic—a blocking high—contributed to the heat wave, which saw temperatures reach 32° C in the northern city of Norlisk. For comparison, daily July highs in Norlisk average 16° C. Blocking highs are so named because they block the jet stream from moving rain-bearing weather systems along their normal west-to-east path; this leads to “stuck” weather patterns with long periods of stable air and exceptional heat.
High temperatures play an important role in promoting wildfires. Warm fuels burn more readily than cooler fuels because less energy is required to raise their temperature to the point of ignition. With temperatures soaring in northern Russia, it was easier for previously active fires to continue burning and for lightning to spark new ones.
This summer’s heat wave, like all extreme weather events, had its direct cause in a complex set of atmospheric conditions that produce short-term weather. However, weather occurs within the broader context of the climate, and there’s a high level of agreement among scientists that global warming has made it more likely that heat waves and wildfires of this magnitude will occur.
While temperatures are increasing globally, the warming in Russia since the mid-1970s has been more rapid than most areas—about 0.51°C per decade compared to about 0.17°C globally—according to a study by Anatoly Shvidenko of the International Institute for Applied Systems Analysis. Researchers expect a doubling in the number of forest fires in Russia’s taiga forests by the end of the century, as well as increases in the intensity of those fires.>>
Please stop.Skeptical Raptor wrote:The problem with the word “skeptic” is that it is used differently in different circumstances, much like the word “theory” has a different meaning in a formal scientific context than it does in common vernacular. To the average person, a skeptic is a person inclined to question or doubt all accepted opinions. In other words, this type of skeptic just doubts everything, whether or not that doubt is backed by any type of evidence. It’s not very meaningful in terms of scientific discussion, and it it carries little weight in a debate about the scientific merits of an idea or a scientific hypothesis.
http://en.wikipedia.org/wiki/Siberian_TrapsA persistent high-pressure weather pattern in the Russian Arctic—a blocking high—contributed to the heat wave
Since you said you love these lists Mark I thought you might like the latest addition to this list: Discovery’s shark week show ‘Megalodon: The Monster Shark Lives’ that aired last night suggested a link between global warming and the possible (read unproven) reappearance of this prehistoric mega shark.mjimih wrote:I love lists like this. It's fun going thru them honestly.
Any show about a magical reappearance of some prehistoric shark (or the loch ness monster, or space aliens, or nostradamus, or mayan style apocalypses, etc) should definitely be looked upon most dubiously. The fact that they threw global warming into the mix isn't even the worst part. They're lowest common denominator shows which feed the drama craving masses. You can easily spot them from the overly dramatic music and hyperactive hosts which successfully create interest in what is otherwise just a bunch of BS.BDanielMayfield wrote:Since you said you love these lists Mark I thought you might like the latest addition to this list: Discovery’s shark week show ‘Megalodon: The Monster Shark Lives’ that aired last night suggested a link between global warming and the possible (read unproven) reappearance of this prehistoric mega shark.
Global warming is real, although its causes are numerous, and not all of them are man made. But when all kinds of ridiculous links are constantly being attached to it the reality of the problem gets suppressed, IMO.
Seriously? Did you forget to add a smiley face?BMAONE23 wrote:Couldn't increased CO2 bring about larger plant yields in the form of the past Mega Flora? Then couldn't this in turn lead to the return of Mega Fauna as stomach sizes and thereby animal sizes would need to increase to accomodate the processing of additional food stuffs.
CO2 enrichment produces greater yields of food crops but produces crops that are slightly more deficient in nutrients thereby creating the need to eat more to attain the same ammount of nutrient intake which in turn would require animals to be larger to have larger stomachs capable of processing a greater food intake.
The return of Mega Flora and Mega Fauna
