The observational confirmation of dark matter. [LINK] Far and away the most important science story for the month, and will definitely be in the top 10 for the year.
This is a great example of how science works. A set of physical rules seemed to make sense, but something didn't fit. Physicists thought they understood how gravity worked (at large scales), but galaxies and clusters of galaxies didn't seem to obey it. It was as if there were more mass that could be measured. A lot of explanations were presented, but one called dark matter seemed to come to the fore. The idea is that there is matter that interacts gravitationally, but we can't actually see it. This conjecture seems to be proved now with observations.
Guess what, science works!
Someone tell Congress.
2006-08-30
Deniers try to misrepresent science.
A nice blog entry has been posted over on Deltoid, of ScienceBlogs [LINK]. It shows Hansen's 1988 climate model predictions of global warming along with observed global temperature. Despite how crude climate models were in 1988, Hansen's predictions are pretty much spot on. It is especially interesting to look at 1993, where the observations take a nosedive because of Mt. Pinatubo. They "recover" in about 2 years. Note that the credit on the figure is to the GISS page [LINK], but neither the blue line nor the extension of the red line (both observations) from 1998 to 2005 is on that page, and I don't know where that data come from. I tend to believe it though. If I find a better reference, I'll post it.
UPDATE: The red line (observations) actually isn't extended. Instead another dataset (blue) is just overlaid.
UPDATE: The red line (observations) actually isn't extended. Instead another dataset (blue) is just overlaid.
2006-08-21
Crutzen's sulfur ideas
"Wait, don't do it!"
That was my first reaction after reading about Paul Crutzen's semi-crazy idea to ameliorate anthropogenic global warming by filling the stratosphere with sulfur. In case you've missed the story, there's a wired article that covers the main points [LINK]. It all stems from an editorial Crutzen published in Climatic Change, [LINK] . The idea is that putting sulfur into the stratosphere (about 20 km above you, say) would reflect sunlight, reducing the amount of energy reaching Earth's surface. That would cool the globe, no doubt, but there are problems.
We know it will work. Volcanoes do this same thing, more or less. We also know it would be temporary, because the sulfur would only float around the stratosphere for a few years before being used up in chemical reactions and slowly deposited back into the troposphere and back to the surface. Crutzen covers all this in the paper, which is mostly a quick back-of-the-envelop calculation mixed with some previous results. Crutzen, it should be pointed out, is not actually in favor of the idea; the media doesn't really seem to be mentioning that so much. In the paper he is extremely hesitant, saying essentially that if we keep pumping CO2 into the atmosphere we may start to experience catostrophic warming (~5 degrees C), which would necessitate rapid action to reduce the global temperature. To that end, he proposes a community wide, multidisciplinary effort to test this geo-engineering scenario. He thinks we need to model the effects, but also consider possible ecological consequences.
So what are the problems with reducing the sunlight getting to the surface? Well, one that is pointed out by the Wired article is that it will directly impact plants and photosynthesis. This might be especially pronounced in the tropics, where plants have evolved to expect a lot of sunlight. Changing the amount of light reaching the surface might give some plants a benefit and others a disadvantage, which could potentially throw the natural balance out of whack. Land-use issues aside, we don't have any idea really what the distribution of plant species in the tropics means for the global carbon cycle, not to mention the hydrological cycle. A second potential problem is that the additional sulfur in the stratosphere might change the stratospheric heating rates, which would change the temperature distribution, which would alter the large-scale temperature gradients, and might impact the Brewer-Dobson circulation. This would have unknown effects on the general circulation of the midlatitudes, possibly altering large-scale weather patterns (think El Nino or North Atlantic Oscillation). A third issue, also mentioned by Crutzen, is that cooling the surface won't save the ocean. As CO2 increases, it will continue to be taken up by the ocean. Unfortunately, that increases the acidity of the upper ocean, where lots of little creatures grow. Many of those little creatures grow calcium carbonate shells, but they can't do it in acidic conditions. That means they die. Not only do those organisms play an important role in the carbon cycle (and other biogeochemical cycles), but they are also the foundation of the entire marine food chain. If they die, then large species suffer, and larger ones suffer even more, and even humans who like to eat seafood will suffer.
So those are my first three potential problems with this plan. However, I'll take Crutzen's side. He basically says that our policy makers have their heads in their behinds, partly because they don't have good solutions and partly because they are not forward thinking, and so there is not going to be a reduction in greenhouse gas concentrations any time soon. Since we know we will face global warming, we need to figure out what to do if the warming starts to get out of control. This sulfur parasol effect is one possibility, and it should be investigated. Along the way, we will continue to learn important things about the climate system, even if the sulfur parasol turns out to be an untenable solution.
Additional reading
1. BioEd Online: Should we flood the air with sulphur? [LINK]
2. Crutzen, Paul J., 2006: Albedo Enhancement by Stratospheric Sulfur Injections: A contribution to resolve a policy dilemma? Climatic Change doi: 10.1007/s10584-006-9101-y [possible LINK]
3. Geo-engineering in vogue, on RealClimate [LINK]
That was my first reaction after reading about Paul Crutzen's semi-crazy idea to ameliorate anthropogenic global warming by filling the stratosphere with sulfur. In case you've missed the story, there's a wired article that covers the main points [LINK]. It all stems from an editorial Crutzen published in Climatic Change, [LINK] . The idea is that putting sulfur into the stratosphere (about 20 km above you, say) would reflect sunlight, reducing the amount of energy reaching Earth's surface. That would cool the globe, no doubt, but there are problems.
We know it will work. Volcanoes do this same thing, more or less. We also know it would be temporary, because the sulfur would only float around the stratosphere for a few years before being used up in chemical reactions and slowly deposited back into the troposphere and back to the surface. Crutzen covers all this in the paper, which is mostly a quick back-of-the-envelop calculation mixed with some previous results. Crutzen, it should be pointed out, is not actually in favor of the idea; the media doesn't really seem to be mentioning that so much. In the paper he is extremely hesitant, saying essentially that if we keep pumping CO2 into the atmosphere we may start to experience catostrophic warming (~5 degrees C), which would necessitate rapid action to reduce the global temperature. To that end, he proposes a community wide, multidisciplinary effort to test this geo-engineering scenario. He thinks we need to model the effects, but also consider possible ecological consequences.
So what are the problems with reducing the sunlight getting to the surface? Well, one that is pointed out by the Wired article is that it will directly impact plants and photosynthesis. This might be especially pronounced in the tropics, where plants have evolved to expect a lot of sunlight. Changing the amount of light reaching the surface might give some plants a benefit and others a disadvantage, which could potentially throw the natural balance out of whack. Land-use issues aside, we don't have any idea really what the distribution of plant species in the tropics means for the global carbon cycle, not to mention the hydrological cycle. A second potential problem is that the additional sulfur in the stratosphere might change the stratospheric heating rates, which would change the temperature distribution, which would alter the large-scale temperature gradients, and might impact the Brewer-Dobson circulation. This would have unknown effects on the general circulation of the midlatitudes, possibly altering large-scale weather patterns (think El Nino or North Atlantic Oscillation). A third issue, also mentioned by Crutzen, is that cooling the surface won't save the ocean. As CO2 increases, it will continue to be taken up by the ocean. Unfortunately, that increases the acidity of the upper ocean, where lots of little creatures grow. Many of those little creatures grow calcium carbonate shells, but they can't do it in acidic conditions. That means they die. Not only do those organisms play an important role in the carbon cycle (and other biogeochemical cycles), but they are also the foundation of the entire marine food chain. If they die, then large species suffer, and larger ones suffer even more, and even humans who like to eat seafood will suffer.
So those are my first three potential problems with this plan. However, I'll take Crutzen's side. He basically says that our policy makers have their heads in their behinds, partly because they don't have good solutions and partly because they are not forward thinking, and so there is not going to be a reduction in greenhouse gas concentrations any time soon. Since we know we will face global warming, we need to figure out what to do if the warming starts to get out of control. This sulfur parasol effect is one possibility, and it should be investigated. Along the way, we will continue to learn important things about the climate system, even if the sulfur parasol turns out to be an untenable solution.
Additional reading
1. BioEd Online: Should we flood the air with sulphur? [LINK]
2. Crutzen, Paul J., 2006: Albedo Enhancement by Stratospheric Sulfur Injections: A contribution to resolve a policy dilemma? Climatic Change doi: 10.1007/s10584-006-9101-y [possible LINK]
3. Geo-engineering in vogue, on RealClimate [LINK]
2006-08-16
cheap movies
Having just spent my second consecutive night appreciating Brick on DVD, I wanted to take a moment out of our usual foray into climate science to talk about movies. A few posts ago, I raved a little bit about Clerks II, which I still highly recommend, but today I want to do something different. I've always appreciated low budget, indie movies, but I've recently seen a few that really struck my fancy. These have also mostly been first efforts (or at least first feature films) from the writer/directors. These are movies that you watch, or at least I watch, and then I just have to wonder how they got it done for hardly any money, and unde adverse filmmaking conditions. My intention is not to review or analyze these films, but just to note them, marke them as different from most movies, even different from most "indie" movies. I'm no expert on this, of course, but I can name a couple off the top of my head. Please feel free to add/recommend movies I've missed.
UPDATE: I just realized that The Brothers McMullen (1995) by Ed Burns was made for just $23,800. I haven't actually seen it, but I know a lot of people swear by it.
- El Mariachi (1992) - Robert Rodriguez - $7,000
- Clerks (1994) - Kevin Smith - $27,000
- Primer (2004) - Shane Carruth - $7,000
- Brick (2005) - Rian Johnson - $500,000
- Honorable mentions:
- Slacker (1991) - Richard Linklater - $23,000
- Texas Chainsaw Massacre (1974) - Tobe Hooper - $84,000
- Roger & Me (1989) - Michael Moore - $160,000 (but it is a documentary)
- THX 1138 (1971) - George Lucas - $777,000 (a little pricey)
UPDATE: I just realized that The Brothers McMullen (1995) by Ed Burns was made for just $23,800. I haven't actually seen it, but I know a lot of people swear by it.
Planets, Dwarf planets, plutons, and apathy
The international astronomical union is going to vote on a new system for classifying heavenly bodies as planets [LINK]. Essentially the new rule is if a thing orbits a star, but is not a star or a moon, and it has enough mass to make it round, then yes, it is a planet. Well done, boys. Here's a potential new schematic of the solar system (LATimes):
People always have to make up labels and categories, despite the fact that nature certainly has shades of grey. We deal with it in clouds classification schemes all the time... cumulus, altocumulus, altostratus, cirrostratus, stratocumulus, and it goes on ad nauseam. Some things are categorized easily. Mammals are different from birds, and both are different from reptiles. Animals are different from plants. Galaxies are different from stars, and both are different from rocks (planet or not). Water clouds are different from dust clouds. Lakes are different from oceans. You get my point. Yet, at some level, the system starts to break down. Is Pluto a planet? Is Ceres? Does it matter what we call them at all? Is this the right way to spend our time? Instead of arguing over whether to have an official definition for planet or dwarf planet or "pluton," why don't we get back to work and figure out some meaningful scientific questions. As for elementary school science books, well, if you grew up in public schools like I did, you know it doesn't matter what the new books say, because the students won't see them until they are obsolete too.
People always have to make up labels and categories, despite the fact that nature certainly has shades of grey. We deal with it in clouds classification schemes all the time... cumulus, altocumulus, altostratus, cirrostratus, stratocumulus, and it goes on ad nauseam. Some things are categorized easily. Mammals are different from birds, and both are different from reptiles. Animals are different from plants. Galaxies are different from stars, and both are different from rocks (planet or not). Water clouds are different from dust clouds. Lakes are different from oceans. You get my point. Yet, at some level, the system starts to break down. Is Pluto a planet? Is Ceres? Does it matter what we call them at all? Is this the right way to spend our time? Instead of arguing over whether to have an official definition for planet or dwarf planet or "pluton," why don't we get back to work and figure out some meaningful scientific questions. As for elementary school science books, well, if you grew up in public schools like I did, you know it doesn't matter what the new books say, because the students won't see them until they are obsolete too.
2006-08-11
A new feature here on FtF
If you ever scroll down the page, take note of a new feature here on Facing the Fire: "An Idiot List." It is just a static list of people, especially those in the media, who consistently seem to say stupid things about climate change. It's not comprehensive, of course, and I welcome suggestions. It's also not a "deniers hit list," even though I did have to add Pat Michaels. I'll be expanding the list as new idiots appear, so keep your eyes peeled.
2006-08-09
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