Maybe you should re-examine your setup if you're having pointing issues. I haven't had any noticeable pointing problems since I got my sensor bar properly centered and calibrated the sensitivity. The only time I have real issues is if there's any other significant IR source nearby or I don't move my glass coffee table out of the way (the sensor bar reflects off of it and the Wii remote gets confused by other IR sources fairly easily).
Yes, I would say Nintendo has figured out "rock solid" engineering with the Wii remote. I mean, what other consumer electronic can you hurl through objects (i.e. tv screens, windows, walls, people's head) and it's still functional?
What you are referring to has been done and is still a very large work in progress, it's called the NCEP/NCAR Reanalysis Project. There is a problem with divergence of these models over time as far as the specific weather predictions for a given day (hence they are averaged in ensemble and reinitialized when they begin to diverge from actual data) due to the problem of incomplete coverage. Because climate is a non-linear system, if your initial conditions don't exactly match (which they never can) your model will eventually diverge (i.e. the "butterfly effect"). But given that, the models still get the general trends correct even if they can't predict it will rain 2" on Tuesday Feb. 14 2010 in Seattle.
Assumptions in climate models aren't "I think snow is reflective, I'll assign it arbitrary albedo x". Rather, assumptions in models consist of "We don't have the resolution to compute convective cells down to the atomic level (or even 1m resolution), so we'll approximate updrafts and cloud formation and precipitation with these simplified physics schemes that we justify based on series of observations A, theory B, and high resolution model of convections C (based on theory B)". A lot of careful analysis goes into every simplifying assumption. And just remember, not all assumptions are bad; after all, Newtonian physics is simply based on the assumption you're moving drastically slower than the speed of light.
And to address your problem with short-term forecasting, there's a world of difference between predicting if it will rain two weeks from now vs. long-term trends. Day to day weather is highly chaotic, but the long-term trends are usually quite predictable. No GCM on Earth will give you accurate weather a month from now, but it can tell you what it's likely to be. Especially given that modern GCMs often spontaneously create natural observed oscillations of Earth's climate out to multi-decadal scale gives us some confidence they're a useful endeavor for looking at climate.
Therein is the beauty of ensemble forecasting. Generally these predictions are made from ensembles of models ranging from simple 1-D radiative transfer models all the way up to complex fully 3-D GCMs used for long-term weather forecasting. Each of these models makes varying assumptions about things like clouds and particulates (if they're included at all). Some models include the 11-year sunspot cycle, some don't. The point is that if all of the models, given their varied complexities and treatments of feedbacks, point to a warmer Earth with increased CO2 thats strong evidence for a positive feedback between CO2 and temperature. I'll concede few of the models agree on concrete predictions (i.e. Europe will get warmer and wetter, the American west becomes even drier, etc.), but the global average temperature does go up. So, irrespective of what the sun is or isn't doing, we have good evidence we're a contributing factor to warming.
As far as what to do about it, that's a political argument, but in general scientists would argue to err on the side of caution and mitigate our impact until it is fully understood. The cost of reducing our CO2 output is a drop in the bucket given the short-term irreversibility of what we're doing and the potential future cost if the dire predictions do come true. Think of it as home insurance: sure it sucks to write out the check every month and feels like a waste of money, unless your house burns down in which case you're glad to have it.
You make a good point that correlation != causation, which is a point drilled into just about every student of climatology at some point (at least this was true for me). However, in this case the belief of global warming has far less to do with statistics than with predictive modeling. To first order, the appealing logic behind global warming goes something like this:
Fact 1: CO2 is a good absorber of IR radiation
Fact 2: We have been increasing concentrations of CO2 in the atmosphere
Fact 3: Historical records compiled from ice cores, tree rings, and coral samples from all over the world indicate a correlation between CO2 and temperature
Deductive hypothesis: To first order, increasing CO2 will increase temperature
Caveat: Climate is complicated and non-linear with lots of feedbacks, best to create some computer models to study it
Now fast forward many years and several iterations of climate models and research into feedbacks and sensitivity and still our simulations predict that average global temperature is increasing. However, this isn't really the most notable result of the models. The alarming result is that in most of the models weather patterns themselves become increasingly erratic with changes to precipitation distribution and extreme swings in local weather.
Climate science is a good deal more complicated than "I observe X and Y to be correlated, therefore if I increase X I also increase Y." Every good scientist is aware of this logical fallacy, but we're also aware it makes a good starting point for investigation, with the catch that you need to be careful to thoroughly test for causality.
You're on the money from what I can find out. You might find this interesting. It saved me from making the mistake of going for a 1080p set when I looked at the size of TV I could fit in my entertainment cabinet (46" or less) and my viewing distance (12 ft).
I think Tower Records suffered from the big boxes like Walmart and Best Buy flexing their corporate muscle more than online piracy. When selling physical media + accessories is your only game you aren't left with the resources to fight a company like Best Buy in a pricewar when they decide to sell CDs $3 or $4 cheaper than you can and make up the difference by selling you a shiny plasma TV. I would maybe buy piracy as an excuse if suddenly Best Buy or Target or whomever suddenly decided CDs were no longer worth selling, but that hasn't seemed to happen.
Funny... I live in LA. I had a hell of a time getting my hands on a Wii and still haven't seen any "lying around". Gamestop only gives me this when I try to look up the Wii. Strangely, when I go look at the PS3 I get this, so I enter my ZIP (90028) and discover I could have picked one up when I was in Pasadena earlier today, in Eagle Rock when I hang out with a friend later, or I could drive 6 miles to Baldwin Hills if I want to go to the nearest store. Where are these Wiis you speak of? I have friends who would like to find this mythical stockpile.
This is one of the most over blown, and overly debunked, myths populated. Find a peer-reviewed climatology paper suggesting anything of the sort as an imminent event, I dare you. Many people have observed that Earth *should* be returning to ice age conditions in the future based on past cycles, but that is a very slow descent. I have yet to see any credible evidence of scientists saying the next ice age was going to happen in a decade. On the other hand, the interaction of CO2 with radiation is well established, and a priori analysis suggests doubling the amount of CO2 in our atmosphere just might have some impact. So maybe we should think twice before drastically altering the concentration of the dominant greenhouse gas on our planet.
They wouldn't see anything. Hubble can just barely make out Pluto's newly discovered 2nd and 3rd moons, and the Voyagers are a hell of a lot smaller and much much further away.
I worked on this project as a grad student at Caltech, so I think I may actually have something useful to add. The reason we care is that Titan is the only other body in the solar system to exhibit anything remotely analogous to a hydrological cycle at Earth-like atmospheric pressure, and with observable surface geology. This is useful because it gives us a solar system analog to weather, hydrology, and hydrological weathering; which will benefit us in understanding how our own planet works. The only other planets that are remotely similar are Venus and Mars, which aren't that similar. If you can get past the temperature issue and replace water with methane/ethane Titan has the most Earth-like atmosphere of any other planet. That's why this is a big deal.
Well it is a situation about any area when a person talks beyond their areas of experties
I was going to make a snarky comment about your expertise in this subject, especially regarding your literature analogy, and then I just didn't have the heart.
Best Buy and Target and the like only seem to have kiosks, but I've seen quite a few "gaming" stores like EB games that have demo consoles set up they'll let you play if you ask.
I was under the impression this is where a lot of people find love, but in a Disney movie? That sounds about as probable as the average/. reader finding love in the back seat of a car...
It seems a relatively new phenomenon these days, where scientist think they have some sort of carte blanche to purpose something, and expect the world to spin around on a dime and provide huge federal grants to modify everyone's behavior. If you ask me it is more than a little disingenious.
Clearly you've never worked at any sort of research institution doing science that was supported by federal grants. If you lack firsthand experience or concrete evidence of this you can cite, I would kindly ask you to shut up before you sound like a bigger idiot.
The idea that the northern hemisphere craters were simply buried is actually a fairly old idea, even though the article makes this sound like a major breakthrough. We've had some radar images suggesting this for some time, I guess it's just now they're starting to get some press. The layered deposits are also well documented, but I do have to admit those are the prettiest pictures I've ever seen of them.
In order to determine correlation/causation in computer models you always do a control run. So, if you wanted to test whether increasing CO2 results in a warmer planet, you would start two models with the same input parameters except one would have CO2 increasing (or start at an increased level) whereas the other wouldn't. If the model with increased CO2 stabilizes at a warmer temperature and the model without increased CO2 continues to look like present-day earth, you could conclude (after sufficiently many trials to determine error) that CO2 results in a warmer planet.
Actually, Titan's atmosphere is the most similar to Earth's of any body in the solar system. Titan is the only other body in the solar system with an atmosphere primarily composed of nitrogen (around 80-90%) and with a similar pressure (1.5 bar to our 1 bar). It just happens to be really really cold there.
It's positive because the effect is self-reinforcing. For example, sea ice melts, exposes ocean which is better at absorbing sunlight, metls more sea ice, etc. An example of a negative feedback is temperature rises, evaporation increases, more clouds form reflecting more sunlight, temperature decreases, less evaporation, fewer clouds, etc. Positive feedbacks tend to run away at exponential rates, negative feedbacks tend to be self-correcting and oscillatory.
This is why most studies don't use just one model. We typically use several models, each using different feedbacks to test their impact on the model. Even if two models do use the same physics, they may have slightly different schemes for handling them (ie cloud physics is particularly tough). Most published climate predictions are ensemble predictions, the average over many different models predicting the same thing. This tends to smooth out biases one particular model or another may have. Typically, a result is assumed to be robust if it shows up consistently in different models of varying complexity. Sea ice is one of those things that always shows up as a feedback loop between some range of parameters in most models, and once you cross the tipping point it's very easy to go from a stable equilibrium with some ice to one of two extremes: no ice or all ice.
Slashdot Mirror
Maybe you should re-examine your setup if you're having pointing issues. I haven't had any noticeable pointing problems since I got my sensor bar properly centered and calibrated the sensitivity. The only time I have real issues is if there's any other significant IR source nearby or I don't move my glass coffee table out of the way (the sensor bar reflects off of it and the Wii remote gets confused by other IR sources fairly easily).
Yes, I would say Nintendo has figured out "rock solid" engineering with the Wii remote. I mean, what other consumer electronic can you hurl through objects (i.e. tv screens, windows, walls, people's head) and it's still functional?
What you are referring to has been done and is still a very large work in progress, it's called the NCEP/NCAR Reanalysis Project. There is a problem with divergence of these models over time as far as the specific weather predictions for a given day (hence they are averaged in ensemble and reinitialized when they begin to diverge from actual data) due to the problem of incomplete coverage. Because climate is a non-linear system, if your initial conditions don't exactly match (which they never can) your model will eventually diverge (i.e. the "butterfly effect"). But given that, the models still get the general trends correct even if they can't predict it will rain 2" on Tuesday Feb. 14 2010 in Seattle.
Assumptions in climate models aren't "I think snow is reflective, I'll assign it arbitrary albedo x". Rather, assumptions in models consist of "We don't have the resolution to compute convective cells down to the atomic level (or even 1m resolution), so we'll approximate updrafts and cloud formation and precipitation with these simplified physics schemes that we justify based on series of observations A, theory B, and high resolution model of convections C (based on theory B)". A lot of careful analysis goes into every simplifying assumption. And just remember, not all assumptions are bad; after all, Newtonian physics is simply based on the assumption you're moving drastically slower than the speed of light.
And to address your problem with short-term forecasting, there's a world of difference between predicting if it will rain two weeks from now vs. long-term trends. Day to day weather is highly chaotic, but the long-term trends are usually quite predictable. No GCM on Earth will give you accurate weather a month from now, but it can tell you what it's likely to be. Especially given that modern GCMs often spontaneously create natural observed oscillations of Earth's climate out to multi-decadal scale gives us some confidence they're a useful endeavor for looking at climate.
Therein is the beauty of ensemble forecasting. Generally these predictions are made from ensembles of models ranging from simple 1-D radiative transfer models all the way up to complex fully 3-D GCMs used for long-term weather forecasting. Each of these models makes varying assumptions about things like clouds and particulates (if they're included at all). Some models include the 11-year sunspot cycle, some don't. The point is that if all of the models, given their varied complexities and treatments of feedbacks, point to a warmer Earth with increased CO2 thats strong evidence for a positive feedback between CO2 and temperature. I'll concede few of the models agree on concrete predictions (i.e. Europe will get warmer and wetter, the American west becomes even drier, etc.), but the global average temperature does go up. So, irrespective of what the sun is or isn't doing, we have good evidence we're a contributing factor to warming.
As far as what to do about it, that's a political argument, but in general scientists would argue to err on the side of caution and mitigate our impact until it is fully understood. The cost of reducing our CO2 output is a drop in the bucket given the short-term irreversibility of what we're doing and the potential future cost if the dire predictions do come true. Think of it as home insurance: sure it sucks to write out the check every month and feels like a waste of money, unless your house burns down in which case you're glad to have it.
You make a good point that correlation != causation, which is a point drilled into just about every student of climatology at some point (at least this was true for me). However, in this case the belief of global warming has far less to do with statistics than with predictive modeling. To first order, the appealing logic behind global warming goes something like this:
Fact 1: CO2 is a good absorber of IR radiation
Fact 2: We have been increasing concentrations of CO2 in the atmosphere
Fact 3: Historical records compiled from ice cores, tree rings, and coral samples from all over the world indicate a correlation between CO2 and temperature
Deductive hypothesis: To first order, increasing CO2 will increase temperature
Caveat: Climate is complicated and non-linear with lots of feedbacks, best to create some computer models to study it
Now fast forward many years and several iterations of climate models and research into feedbacks and sensitivity and still our simulations predict that average global temperature is increasing. However, this isn't really the most notable result of the models. The alarming result is that in most of the models weather patterns themselves become increasingly erratic with changes to precipitation distribution and extreme swings in local weather.
Climate science is a good deal more complicated than "I observe X and Y to be correlated, therefore if I increase X I also increase Y." Every good scientist is aware of this logical fallacy, but we're also aware it makes a good starting point for investigation, with the catch that you need to be careful to thoroughly test for causality.You're on the money from what I can find out. You might find this interesting. It saved me from making the mistake of going for a 1080p set when I looked at the size of TV I could fit in my entertainment cabinet (46" or less) and my viewing distance (12 ft).
I think Tower Records suffered from the big boxes like Walmart and Best Buy flexing their corporate muscle more than online piracy. When selling physical media + accessories is your only game you aren't left with the resources to fight a company like Best Buy in a pricewar when they decide to sell CDs $3 or $4 cheaper than you can and make up the difference by selling you a shiny plasma TV. I would maybe buy piracy as an excuse if suddenly Best Buy or Target or whomever suddenly decided CDs were no longer worth selling, but that hasn't seemed to happen.
yes, but then you wouldn't have any reason to spend $80 on 4 classic controllers.
Funny... I live in LA. I had a hell of a time getting my hands on a Wii and still haven't seen any "lying around". Gamestop only gives me this when I try to look up the Wii. Strangely, when I go look at the PS3 I get this, so I enter my ZIP (90028) and discover I could have picked one up when I was in Pasadena earlier today, in Eagle Rock when I hang out with a friend later, or I could drive 6 miles to Baldwin Hills if I want to go to the nearest store. Where are these Wiis you speak of? I have friends who would like to find this mythical stockpile.
This is one of the most over blown, and overly debunked, myths populated. Find a peer-reviewed climatology paper suggesting anything of the sort as an imminent event, I dare you. Many people have observed that Earth *should* be returning to ice age conditions in the future based on past cycles, but that is a very slow descent. I have yet to see any credible evidence of scientists saying the next ice age was going to happen in a decade. On the other hand, the interaction of CO2 with radiation is well established, and a priori analysis suggests doubling the amount of CO2 in our atmosphere just might have some impact. So maybe we should think twice before drastically altering the concentration of the dominant greenhouse gas on our planet.
So my grandmother really was trying to kill me when she gave me cod liver oil? I knew it!
Maybe not mentally, but certainly they scarred my retinas. Goatse made me blind you insensitive clod!
They wouldn't see anything. Hubble can just barely make out Pluto's newly discovered 2nd and 3rd moons, and the Voyagers are a hell of a lot smaller and much much further away.
I worked on this project as a grad student at Caltech, so I think I may actually have something useful to add. The reason we care is that Titan is the only other body in the solar system to exhibit anything remotely analogous to a hydrological cycle at Earth-like atmospheric pressure, and with observable surface geology. This is useful because it gives us a solar system analog to weather, hydrology, and hydrological weathering; which will benefit us in understanding how our own planet works. The only other planets that are remotely similar are Venus and Mars, which aren't that similar. If you can get past the temperature issue and replace water with methane/ethane Titan has the most Earth-like atmosphere of any other planet. That's why this is a big deal.
I'm amused by your choice of link. That's the man who taught me introductory physics as an undergraduate. Brilliant researcher, horrible lecturer.
Best Buy and Target and the like only seem to have kiosks, but I've seen quite a few "gaming" stores like EB games that have demo consoles set up they'll let you play if you ask.
I was under the impression this is where a lot of people find love, but in a Disney movie? That sounds about as probable as the average /. reader finding love in the back seat of a car...
Clearly you've never worked at any sort of research institution doing science that was supported by federal grants. If you lack firsthand experience or concrete evidence of this you can cite, I would kindly ask you to shut up before you sound like a bigger idiot.
The idea that the northern hemisphere craters were simply buried is actually a fairly old idea, even though the article makes this sound like a major breakthrough. We've had some radar images suggesting this for some time, I guess it's just now they're starting to get some press. The layered deposits are also well documented, but I do have to admit those are the prettiest pictures I've ever seen of them.
In order to determine correlation/causation in computer models you always do a control run. So, if you wanted to test whether increasing CO2 results in a warmer planet, you would start two models with the same input parameters except one would have CO2 increasing (or start at an increased level) whereas the other wouldn't. If the model with increased CO2 stabilizes at a warmer temperature and the model without increased CO2 continues to look like present-day earth, you could conclude (after sufficiently many trials to determine error) that CO2 results in a warmer planet.
Actually, Titan's atmosphere is the most similar to Earth's of any body in the solar system. Titan is the only other body in the solar system with an atmosphere primarily composed of nitrogen (around 80-90%) and with a similar pressure (1.5 bar to our 1 bar). It just happens to be really really cold there.
It's positive because the effect is self-reinforcing. For example, sea ice melts, exposes ocean which is better at absorbing sunlight, metls more sea ice, etc. An example of a negative feedback is temperature rises, evaporation increases, more clouds form reflecting more sunlight, temperature decreases, less evaporation, fewer clouds, etc. Positive feedbacks tend to run away at exponential rates, negative feedbacks tend to be self-correcting and oscillatory.
This is why most studies don't use just one model. We typically use several models, each using different feedbacks to test their impact on the model. Even if two models do use the same physics, they may have slightly different schemes for handling them (ie cloud physics is particularly tough). Most published climate predictions are ensemble predictions, the average over many different models predicting the same thing. This tends to smooth out biases one particular model or another may have. Typically, a result is assumed to be robust if it shows up consistently in different models of varying complexity. Sea ice is one of those things that always shows up as a feedback loop between some range of parameters in most models, and once you cross the tipping point it's very easy to go from a stable equilibrium with some ice to one of two extremes: no ice or all ice.