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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
The difference is that on mars, you have no atmosphere. In the UK its usually cloudy, and it often rains. This keeps the temperature, even during the night. On mars its like in a desert (just way more worse): if the sun goes down, it gets cold immediately.
No atmosphere? It most definitely has an atmosphere.
https://en.wikipedia.org/wiki/...
Do not look at laser with remaining good eye.
The warmunists don't say warming is bad for life. They say the rapidity of the warming is gonna be bad for humans.
Yes of course, we're all slaves to the corrupt and powerful environmentalist cartel.
As opposed to the poor, impoverished oil and gas industry, which is clean as a whistle and barely getting by.
Only crack the nuts that crack. You don't put the ones that don't crack in the sack.
Just because similar things happen on two planets doesn't mean that the reason for this cannot be two different things.
In other words, just because there's volcanoes on Io and on Earth doesn't mean Earth in in the gravitational stranglehold of a huge mass nearby.
We used to have a Bill of Rights. Now, with the rights gone, all we have left is the bill.
TFA:
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.
For Earthlings, the Martian atmosphere is a fairly good vacuum.
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.
The Sun waves hello from a mere 93 million miles away...
"Wait. Something's happening. It's opening up! My God, it's full of apricots!"
But, the writers can't come up with a relate-able peril scene to set the emotional stage for abandoning the crew member without a powerful storm that put the ship in jeopardy.
The Martian was a great movie, as long as you didn't think about it.
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.
Yes, the atmospheric gases move at hundreds of miles per hour in a storm
You do realize that the load from wind is the square of the wind speed times density? And the density would be increased by the dust that was picked up? At the height of summer, effective density of 0.01 atm and 175 kph wind speed (sited by the book and film, but could be higher during gusts), that would be 15 newtons per square meter. A fragile high surface area rocket which is not well secured would have a significant side force which could indeed push it over.
I haven't watched the movie so I don't know just how much force they portray from the wind storm. But wind speeds that high are not something to trifle with even in Mars's far less dense atmosphere.
Bush. It was Bush.
'Republicans must exist there!' is an easy first conclusion, but so far we haven't imaged any golf courses.
Could anyone genuinely be this much of a moron?
I wasn't sure about the scientific value of his argument, but thanks to your in-depth analysis I am now a born-again anti-denier.
lucm, indeed.
Mars' global warming is exactly why we need common sense socio-economic mandates here on earth. I'm so glad to see that a lot of large tech news websites, like Wired and The Verge, spontaneously all wrote articles on the anniversary of "An Inconvenient Truth."
OK, apparently the answer is "yes", so I'll spell out why the notion is stupid. First, let's be clear what AC is implying: that the fact life thrived under high CO2 Jurassic conditions means that a rapid shift of climate in that direction will be good for the environment. Or at least harmless.
The Jurassic period was over 200 million years ago. Not only did the continents we're familiar not exist, neither did any of the species that currently populate the Earth. In fact major classes and orders of species had yet to emerge. Mammals. Flowering plants -- including all grasses (and that means every cereal crop) and most orders of common trees other than conifers and ginkos. Modern conifers and ginkos of course aren't the same as their ancestors; they've evolved to be adapted for modern conditions.
For that matter every single species currently living on Earth has evolved over the last two hundred million years to thrive and compete in a low CO2, lower O2 atmosphere than in the Jurassic. If you could wave a magic wand and instantly restore Jurassic atmosphere the result would be rapid, mass extinction of most of the species familiar to us. This won't largely be due to individual plants not surviving, but in a massive competitive advantage for plants on the right end of the bell curve for being able to exploit these conditions. Naturally this would be accompanied by massive animal die-offs. Many animals will die off due to direct effects (ocean acidification), others by having the plants they depend on directly or indirectly disappear. This in turn will result in more plant species extinction as animal species they depend upon disappear.
The higher oxygen levels will also hurt some species. O2 isn't just necessary to life, it's also toxic to life at high partial pressures. The level at which it is toxic to humans is slightly higher than Jurassic levels, but many other species won't tolerate it. It's just like water; all plants need water, but watering some plants too much will kill them.
So the result of a shift to a Jurassic atmosphere wouldn't look much like the Jurassic period. Jurassic ecosystems had evolved over tens and hundreds of millions of years along with the changing levels of CO2 and O2. In our rapid CO2 shift scenario plant life would grow explosively, but not all plant life. Very soon we'd be living in a planet overgrown with weeds. This in fact is just a more severe version of the scenario we're actually facing, in which we lose quite a bit of biodiversity as the atmosphere changes on faster-than-evolutionary timescales. But of course the situation *will* right itself -- in a few million years.
So to recap, you can't compare the effect of CO2 in the modern era to the Jurassic era, because the Jurassic era was 200 million years ago. The sun was different, the continents were different, the species on the planet were different, and all those species had adapted over millions of years to gradual changes in the atmosphere.
It's probably true that there's no reason to prefer living on a planet with 200 ppm CO2 to one with, say, 2000 ppm CO2;but there's every reason to prefer living on a planet where the atmosphere has been changing slow enough for evolution to track.
Post may contain irony: discontinue use if experiencing mood swings, nausea or elevated blood pressure.
Actually, it's Uranus that has that extreme axial tilt. But you are correct, being a resident of the equator on such a planet (if it were rocky, and you were OK with temperatures that varied by hundreds of degrees) would be interesting.
Gamingmuseum.com: Give your 3D accelerator a rest.
You're mostly correct, but there are many species that have existed since the Jurassic and before, e.g. coelacanath, sturgeon, horseshoe crab, and some jellyfish. As far as plants, there probably aren't many that would be useful to us, but I know for a fact some fern species existed. So your easily-disproved allegation, "neither did any of the species that currently populate the Earth", is incorrect.
Gamingmuseum.com: Give your 3D accelerator a rest.
One of the drivers of climate change, on the scale of 10's to 100's of thousands of years are the regular changes in a planets orbit, eccentricity, axial tilt, whether summer in a hemisphere happens at perihelion etc. This will drive climate change on both the Earth and especially Mars as its orbit is so eccentric. They're named Milankovitch cycles, https://en.wikipedia.org/wiki/...
https://en.wikipedia.org/wiki/Inverted_totalitarianism
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.
Total solar radiation has varied less than 0.2%, comparing the average across the roughly 11-year cycle. It has neither increased nor decreased. What has changed over time os the length of cycle, and the variance in length correlates very closely with global temperature. See the chart here:
http://hyperphysics.phy-astr.g...
You may have noticed that of you fill a bathtub with hot water in the evening, it's still warm the next morning. Water is very good at holding on to heat. (Compare the air in your house, or the furniture, which will cool in minutes). The huge volume of water in the oceans may hold heat for years, such that the length of the solar cycle matters.
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.
So, if you're one of those species, climate change is a big win!
You are welcome on my lawn.
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.
Strawman. I never claimed Earth's climate changes were the result of the same orbital variations as those affecting Mars' climate.
... we're still pretty damn confident that it's the humans
So, humans are to blame for all the previous warming periods in Earth's long climate change history, and long before humans existed and created an industrial society? No way possible these same causes of previous climate changes in Earth's history could be the primary causes and drivers of current changes?
Time traveling climate terrorists from the twenty-fourth-and-a-half century, then? Quick! Somebody call Duck Dodgers!
Strat
Progressivism (aka US 'Liberalism'): Ideas so good they need a police/surveillance-state to enforce.
Here's the long view. Something peculiar happened on Earth about 150 years ago.
Yes. We started measuring global temperatures accurately, with thermometers, instead of using ice core and other proxies. We know that the proxies have much lower resolution than the actual measurements and are not comparable at all, but AGW proponents still plot them on the same graph as thermometer measurements, which makes for this big, scary spike since 1870.
Incidentally, I've read (although I can't remember where, but I'll have to put the effort into finding it sometime) that if you use ice core proxy data for the last 150 years, this spike is completely gone. Meaning, of course, these kind of "unprecedented, rapid" fluctuations could have been happening the entire time, and we'd never know, because we don't have anything other than low resolution proxy data for that time period.
Until the AGW people stop plotting these two completely different datasets on the same graph, they'll have a very difficult time convincing skeptics of the accuracy of the science, since they're doing something that is specifically disallowed in EVERY OTHER SCIENTIFIC DISCIPLINE on the planet.
"City hall" in German is "Rathaus" Kinda explains a few things......