Wildfire tracking is remarkably similar to the tracking of weather systems (at least when seen from the peculiar perspective of mathematics). We followed up:www.ucdenver.edu/about/newsroom/newsreleases/Pages/Exploring...Loren
Did you play up the global warming part to increase your odds of funding or do you actually believe global warming causes more wildfires / firestorms? If you actually believe global warming causes more wildfires / firestorms, what evidence is your belief based on?
Evidence....evidence.... We don' need no stinkin' evidence
jck: Did you play up the global warming part to increase your odds of funding?Our grant application did not mention climate change, global warming, or any related concept. Our entire emphasis is on tracking the movement of the fire line, not on any broader scientific issues.The subject of firestorms and global warming came up in the context of what we cannot do with current woodland fire models. I was trying to give the reporter an idea of the limits of our research program. Despite the interest of the reporter, firestorms and the influence of global warming are completely beyond our scope, and we did not propose to address these subjects. They were never even mentioned, and properly so.It may help to remember that this is not a grant in atmospheric physics, nor is it climate science. We are merely mathematicians, seeking funding from the math division of NSF. Perhaps it may help to present our project summary here. The core idea of the proposal is in the second paragraph below.Intellectual merit. This project will develop new methods for data-driven scientific computing. These methods will build on the principles of statistical data assimilation, which adjusts the state of a model in response to new data, while the model is running. Related methods are used in artificial intelligence, such as robotic vision, and many other areas. New methods for the estimation of the model state covariance, accelerated by the use of wavelets, will allow the treatment of large problems with many millions of variables on a laptop instead of a supercomputer. The new methodologies exploit the synergy of theory of random fields in spatial statistics with the power of Bayesian modeling and spectral analysis. The basic approach is that of ensembles, which are collections of independent simulations, which approximate the probability distribution of the model state. Since the targeted application is numerical solution of partial differential equations, the ensemble members are very large — easily millions of degrees of freedoms — which makes large ensembles impractical. Unlike sequential Monte Carlo methods, which require very large ensembles with thousands of members, and ensemble Kalman filters, which require tens or hundreds of members, the proposed wavelet-based methods could reduce the required ensemble size to just a handful of members.A common feature of ensemble methods is that their accuracy increases with the ensemble size, and the investigators have already proved an asymptotic convergence with the ensemble size to the correct probability distribution in the finite dimensional case. Theoretical analysis of the ensemble methods in this project centers on the issue of stochastic convergence in the case of both high dimension of the system and large number of ensemble members. The general approach will be to prove the convergence in the large ensemble limit in infinitely dimensional spaces first, then consider the high-dimensional case as an approximation of the infinitely dimensional case, much as in standard error analysis of the numerical solution of partial differential equations, except that the convergence is stochastic spaces. Connections between probability measures on Sobolev spaces, random fields in spatial statistics, stochastic expansions will be exploited to effectively reduce the dimensionality of the system.The application area of the project is data assimilation for coupled atmosphere-wildland fire models. While Bayesian data assimilation for the fire spread itself is amenable to variants of classical Monte-Carlo approaches, the high dimension of a coupled weather-fire model makes such methods infeasible. The investigators have already developed methods for position correction, which transform the state probability distribution closer to Gaussian in problems with coherent features, such as firelines, thus making Kalman filer type methods feasible. An additional challenge is that the state of the atmosphere must be consistent with the state and the intensity of the fire, and the influence of the fire builds up over time. Rather than modifying the state directly, this project will seek to modify the state of the fire model and then catch up with the evolution of the atmosphere, thus avoiding incompatibilities of the coupled model state.Broader impact. This project will have impact on the state of the art of modeling wildland fires. Wildfires present a serious danger and cause significant damage every year, and managing wildland fires is a challenge of great importance to the society. The project will involve undergraduate and graduate students in seminars and classes, and K-12 students at STEM outreach events. The project will support a PhD student and a postdoc. The investigators will reach out to existing programs for successful participation of underrepresented groups in STEM-related disciplines, and their alumni will be strongly considered for involvement in this project.Loren
shotzongoal: Evidence... evidence... We don' need no stinkin' evidence!Evidence of what?That our mathematics is correct? You can verify that for yourself, all of our work is in the public record. Here are the key papers:http://arxiv.org/abs/0901.2951http://arxiv.org/abs/1102.5554We actually now have two different ways of proving the convergence result, and a third was found by a French team last year. This leads us to believe that we are on the right track.Or did you want evidence that higher air temperatures cause the probability of wildfires to increase? That particular idea is backed up by an impressive body of evidence. Wikipedia summarizes the known facts here:http://en.wikipedia.org/wiki/Wildfire#Effect_of_weatherOr, if you like, you can refer to the scientific literature:D McKenzie, Z Gedalof, DL Peterson, and P Mote (2004) "Climatic Change, Wildfire, and Conservation", Conservation Biology, vol 18, pp 890-902. DOI: 10.1111/j.1523-1739.2004.00492.xAvailable online at onlinelibrary.wiley.com/doi/10.1111/j.1523-1739.2004.00492.x...Loren
What evidence is YOUR belief based on Jack? You aren't being reasonable here. You are just sniping for the sake of it and really should have self-censored that post... much as I have self-censored 2 previous responses to you here.Loren has been patient with you and ShotzOnGoal. All he posted was about the mathematical similarities... and you just HAD to insinuate that he was doing something for the money? How bitter are you planning to get?
Jack has been a bitter troll for years:http://boards.fool.com/jck-quotyou-are-under-no-obligation-t...
The subject of firestorms and global warming came up in the context of what we cannot do with current woodland fire models. I was trying to give the reporter an idea of the limits of our research program. Despite the interest of the reporter, firestorms and the influence of global warming are completely beyond our scope, and we did not propose to address these subjects. They were never even mentioned, and properly so.Here is where my confusion is then:"There's some similarity between epidemics of infectious diseases and wildfires," Cobb said. "They both need fuel. In the cases of an epidemic the fuel is people who are susceptible to a disease. .. The spatial pattern as it moves across a continent is similar. Where they depart is the phenomenon of a firestorm. A firestorm is a wildfire gone crazy and it has its own special dynamics that a wildfire doesn't have."He added, "nobody is looking forward to the kinds of firestorms that global warming may bring. If we have hotter weather and a drier climate and trees being killed by beetles -- that's a bad combination."So obviously global warming was brought up and to me it looked like an add in for whatever reason which is why I asked the question (plus this is the climate change board).
What evidence is YOUR belief based on Jack? You aren't being reasonable here. You are just sniping for the sake of it and really should have self-censored that post... much as I have self-censored 2 previous responses to you here.Loren has been patient with you and ShotzOnGoal. All he posted was about the mathematical similarities... and you just HAD to insinuate that he was doing something for the money? How bitter are you planning to get?I'm pretty sure Loren is doing something for money or he didn't even need to bother applying for grants, just do the research. Anyway, like I said in my previous post it did look like an add in. I'm also not aware of any link between AGW and fires, which is why I asked for evidence.I wasn't sniping, I was asking an honest question.
Jack has been a bitter troll for years:You've been making incorrect assumptions about me for 4 years at least. I apologized for that post later on in the thread.
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