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Mars Is Coming Out Of An Ice Age (reuters.com)
Taco Cowboy quotes a report from Reuters: An analysis of radar images that peered inside the polar ice caps of Mars shows that Earth's neighbor is coming out of an ice age that is part of an ongoing cycle of climate change, scientists said on Thursday. Using images taken by satellites orbiting Mars, the researchers determined that about 20,872 cubic miles (87,000 cubic km) of ice has accumulated at its poles since the end of the ice age, mostly in the northern polar cap. Scientists are keenly interested in piecing together the climate history of Mars, which contains strong evidence that oceans and lakes once pooled on its surface, bolstering the prospects for life. From the perspective of an Earthling, every day on Mars may feel like an ice age. According to NASA, temperatures on Mars may hit a high at noon at the equator in the summer of roughly 70 degrees Fahrenheit (20 degrees Celsius), or a low of about minus-225 degrees Fahrenheit (minus-153 degrees Celsius) at the poles. The Martian ice began its retreat about 370,000 years ago, marking the end of the last ice age, according to the research published in the journal Science
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Since we've already accounted for the effect of Earth's orbit and tilt (which run on 100,000 and 20,000 year cycles), unless you have a bitchin' theory for how Mars' orbit and tilt afffect the climate of the Earth, we're still pretty damn confident that it's the humans.
I did some looking into the effects of solar changes on global and solar-system temperatures, because I wondered how much of an effect it might have, if any.
I know most people are already fans of a certain "team" when it comes to global warming / climate change, so they are more interested in bulstering their original guess than learning more information, but those those who are curious here's what I found out. Temperatures on the other planets have, on average, risen less than on earth, but they have risen some. It's hard to be certain, but a reasonable estimate is that changes in the sun might account for 25%-35% of the warming we've seen on earth.
Digging through all the propaganda and distorted data on AGW is difficult, but there seems to be pretty good evidence to support the notion that 25%-35% is caused by increased CO2, caused both by fossil fuel use and deforestation. Deforestation also increases average daily high temperatures more directly by reducing evaporative cooling during the hottest part of the day (and corresponding rain).
That leaves about 40%-50% of the increase that can't be clearly attributed to any specific cause. Objective research by people not funded by political entities would be helpful.
Very true. Well, if you are a poikilothermic animal, that is. Or if you're an insect and would like to grow larger. Because that's pretty much not possible with petty oxygen levels of about 20%. You should also not be living near a shore, unless you're an aquatic animal (but if you are, life's going to be great... provided you're not too dependent on, you know, a shore).
So yeah, life would be a lot better if conditions were again as they used to be back then. If you're a lizard. Or a dragonfly. Or a fish.
Huh? You're a human? Boy, sucks to be you!
We used to have a Bill of Rights. Now, with the rights gone, all we have left is the bill.
Look, if you can't even do the match correctly on this, you have no business giving your input on this.
I hate when this happens to me. Just yesterday I didn't do the match correctly and I ended up wearing a brown belt with my black shoes, I looked stupid all day.
lucm, indeed.
I considered the "living fossil" argument, but in general the "living fossil" thing is a bit misleading. When organisms are discovered living that are known from the fossil record (or vice versa), initially the public news is that a "living fossil" has been discovered, but then the systematics geeks get to work and the modern and fossil versions end up classified differently. They continue to be promoted as "living fossils" to a public that needs every encouragement to care about science and the environment, but researchers generally have a more nuanced view than the simple but romantic picture of a population that has remained totally unchanged for millions of years. That just doesn't happen.
The "living fossil" par excellence is of course the Coelecanth. However in the 80 years since the first living example was discovered, living Coelacanths have been placed in a separate genus (Latimeria) from any example in the fossil record. The anatomical resemblances between Latimeria and fossil genera are striking, amazing even. The differences perhaps may be too subtle for a layman to discern, but to a taxonomist they're there. Same goes for horseshoe crabs, ginkgos, etc.
If you think about how genetics works, the idea that a species could be a stable construct over millions of years is extremely implausible. Even if you can't see an anatomical distinction, if you had a time machine and brought back a DNA sample it's bound to put the ancient population in a different taxon just by genetic drift alone. That doesn't count selective advantage for mutations that adapt an individual for changing environmental conditions such as heat and gas composition and, for marine organisms, pH.
Post may contain irony: discontinue use if experiencing mood swings, nausea or elevated blood pressure.
I did some looking into the effects of solar changes on global and solar-system temperatures, because I wondered how much of an effect it might have, if any.
Solar output has been dropping over the last several decades. The sun does (obviously) affect the surface temperature, but to the extent that it does it has been driving temperatures DOWN: http://woodfortrees.org/plot/s...
That means something else has been not only counteracting the cooling effect of the sun but also warming the planet at a rate unprecedented in the last 10,000 or so years.
Meanwhile Mars has been coming out of an ice age for the last 370,000 years (according to TFS). There are other factors at play here than just the sun.
Scientists who have attempted to quantify the human contribution to the current temperature rise have found that anthropogenic sources account for between 80% and 150%. See Tett et al. 2000, Meehl et al. 2004, Stone et al. 2007, Lean and Rind 2008, Huber and Knutti 2011, Gillett et al. 2012, Wigley and Santer 2012 , and Jones et al. 2013. It may be unintuitive to think that humans may have cause more than 100% of the current warming, but remember that natural factors have generally been forcing planet towards another glacial period. We've just had the weakest solar cycle in over 100 years. If solar variability is a strong contributor to global mean temperature then other forces have not only caused all of the warming that we have recently observed, but also caused enough additional warming to offset the cooling caused by the sun.