Archive for the ‘computer models’ Category

model and visualize environmental change

Monday, October 16th, 2006

Okay, it’s been awhile. I’m enjoying my sabbatical in the Netherlands so blog activity has slowed way down. But with my recent upgrade of wordpress I’m ready to get started again. Here’s an interesting presentation on a piece of software that has amazing potential for landscape analysis, scenario planning, and participatory planning.

Let’s say, you’re concerned about the impact on erosion of a particular clearcut. You delineate the area, “build” the bulldozer, run the model, and then measure the siltation. Voila, you see your impact.

when video ain’t good enough

Monday, August 21st, 2006

NASA is beginning to use animation techniques from Hollywood to communicate its data, for example, on storms, climate change, and algae blooms.

“Visualization is that link between the flood of data coming down from space and the ability of the human mind to interpret it,” Feldman said. “That’s the crux of the story. Better than most other groups in the world, they are able to take this fire hose of data coming down and turn it into images — visual animation — that then allows the general public to see this data in ways their brains can interpret and study.”

But even computer-aided data visualization is no longer good enough. Got to juice it with some animation.

The Hollywoodization of NASA data is in part the result of Pixar’s success in creating real-life worlds from fantasy stories. People have come to expect that even the most fantastical of ideas — a talking, curmudgeonly Mr. Potato Head — can look and feel exceedingly real. “They don’t expect to see crudity,” Mitchell said. “They expect to see sophistication because they see it everywhere. In order for us to tell the story, we have to be sophisticated about telling stories and we have to use sophisticated technology to tell them.”

On the one hand, you want the public to have a good sense of how storms work or appreciate the urgency of climate change. On the other hand, wouldn’t it be better to get people used to the lack of sophistication of some of the imagery? When does animation stop being a valuable tool and start becoming fakery? Perversely, the use of animation may convince people that everything they see is potentially fake (moon landing anyone?) OR good animation, in the hands of non-scientists, may be so convincing that the public believes the planet is doing fine.

your planet’s warming, but it sure is purty

Sunday, August 6th, 2006

Climate change modelling, if nothing else, is poetic:

The gigantic super-computer in the basement of the National Center for Atmospheric Research in Boulder, Colo., is so big you can walk down the aisles inside it, the walls of the sleek black servers at either elbow, wrapped in the constant hum of air coolers and countless trillions of silicon chip operations working day and night to calculate the climate future over the next several decades of the only home we’ve got: Earth.

Sounds like the scientists are visualizing the results on NASA’s science on a sphere:

With green and blue for cooler temperatures, scientists and regular folks can watch the digitized projectors paint the globe, starting in 1870. Along about 1990, the globe grows yellower — warmer — and is entirely yellow by 2001.

Then comes the sobering part. Red, for much warmer, starts to appear in North America — and other continents — and by 2051 the United States is almost entirely red.

Update: like this addition from ABC News: “Witnessing the impact of global warming in your life? ABC News wants to hear from you.” Wonder what responses they’re receiving.

Canadian math gurus falsify methods used to derive “Hockey Stick”; a revival emerges.

Sunday, July 16th, 2006

A prime example of the public bootlegging of science:

“…discussion of [the ‘Hockey Stick’ global warming curve] has been so polluted by political and activist frenzy that it is hard to dig into it to reach the science. My earlier column was largely a plea to let science proceed unmolested. Unfortunately, the very importance of the issue has made careful science difficult to pursue.” – R Muller, Technology Review – full article here.

The article is a summary of the high-calibre mathematic mystery – does the so-called “Hockey Stick” really portray history’s temperature spiking? No, not really. The standardization technique was blurred into the analysis itself, but the result’s “principal component will have a hockey stick shape even if most of the data do not.”

I would argue that no matter what degree of error was found in the original opus, the “Hockey Stick” concept has made an indellible impression. Public opinion on the matter will not likely let go – just the contrary, it seems that more and more agreement is emerging for rapid global warming.

However, there is a healthy backing from scientists who know more than mere journalistic perspectives: the blog “Real Climate” opened up an extensive back-and-forth that supports the initial findings and message.

new input devices for simulation

Thursday, July 6th, 2006

The project description is here, although the video players are better at veoh and at youtube.

According to the creators,

Since refining the FTIR (frustrated total internal reflection) sensing technique, we’ve been experimenting with a wide variety of application scenarios and interaction modalities that utilize multi-touch input information. These go far beyond the “poking” actions you get with a typical touchscreen, or the gross gesturing found in video-based interactive interfaces. It is a rich area for research, and we are extremely excited by its potential for advances in efficiency, usability, and intuitiveness. It’s also just so much fun!

Our technique is force-sensitive, and provides unprecedented resolution and scalability, allowing us to create sophisticated multi-point widgets for applications large enough to accommodate both hands and multiple users.

The video shows a great example of how the interface could be used with cartography and GIS (e.g., think of how it could be integrated with Google Earth!). I think it has enormous implications for environmental modelling, simulation, presentation and group work. Just think about how it could be used in describing the impacts of climate change or exploring future scenarios in community planning.

impacts of climate change being felt now

Thursday, July 6th, 2006

The Associated Press reports on a recent paper in the journal Science that links wildfires in the Western US to global warming (notice the hedging in the AP article: Wildfires may be linked to global warming). According to the article:

Beginning about 1987, there was a change from infrequent fires averaging about one week in duration to more frequent ones that often burned five weeks or more, they reported. The length of the wildfire season was extended by 78 days.

The researchers said the changes appear to be linked to annual spring and summer temperatures, with many more wildfires burning in hotter years than in cooler years.

They also found a connection between early arrivals of the spring snowmelt in the mountainous regions and the incidence of large forest fires. An earlier snowmelt, they said, can lead to an earlier and longer dry season, which provides greater opportunities for large fires.

The paper is called Warming and Earlier Spring Increases Western U.S. Forest Wildfire Activity. In typical Science magazine style, it is quite readable, albeit brief so if you want further details you have to read other articles by the authors. The authors examined counter-explanations such land-use history (e.g., conversion of forests to grazing that would cause older trees to be cut down to be replaced by younger and skinnier trees called “fuels”) and cyclical changes in temperature (e.g., El-Nino). Their spatial models showed that climate change still was the culprit.

Note also, in the Science article, that climate change doesn’t just mean increasing temperatures but a whole host of interacting changes to the biosphere (FYI: numbers in parentheses below refer to citations in the bibliography):

climatic explanations posit that increasing variability in moisture conditions (wet/dry oscillations promoting biomass growth, then burning), and/or a trend of increasing drought frequency, and/or warming temperatures, have led to increased wildfire activity (13, 14).

On decadal scales, climatic means and variability shape the character of the vegetation (e.g., species populations and their drought tolerance (23), and biomass (fuel) continuity (24), thus also affecting fire regime responses to shorter term climate variability). On interannual and shorter time scales, climate variability affects the flammability of live and dead forest vegetation. (13–19, 25)

About the only quibble I have with the model is the assumptions in fitting different data sets together (technically, downscaling and interpolation) but that’s a problem you have with any large computer model, whether it models urban growth, national security risks, or climate change. (Also, they should have made use of a GIScientist because they would probably have seen even larger correlations if they looked at the data topologically.) Other than these issues, this is powerful evidence that climate change effects are being felt now.

(For those of you who’d like to point out that events, such as permafrost melting in Northern North America, are being felt now, let me amend the previous to be this is powerful evidence that climate change effects are being felt now in places where many people live.)

Update: Argh! CBC TV gets it wrong! CBC covered the article on the national news tonight. In the report, a university professor says that the article did not address the drivers of climate change. True, the authors do not address the issue of whether or not climate change is induced by humans. But then the reporter states that the authors don’t say whether the wildfires are due to cyclical weather patterns or from climate change. No. The article clearly rules out cyclical patterns. So much for our insightful reporters.

so much for my oblate spheroid

Wednesday, June 14th, 2006

NOAA just announced a new projection system that shows rotating spatial data on a sphere. It’s called Science on a Sphere. Four computer controlled projectors (one computer per projector, plus a fifth coordinator computer) project images that appear to move on a six foot spherical movie screen.

Science on a Sphere takes flat, two-dimensional images and data taken from spherical objects like planets and moons, and synchronizes and blends them into animated presentations. Most of the almost 100 presentations created so far are silent displays meant to illustrate lectures.

This is something you have to see, so the NYTimes has a short video on the subject. The NOAA site has the best video, though. My favorite is the x-ray sun. The 500-year CO2 simulator is pretty scary and in-person it must be one of the best visualizations of climate change available.

The system costs a whopping $180,000 for the hardware and software. I’m sure it could be done for cheaper and it could be better as well. Start with a weather balloon for the screen. The stick of gum-sized Linux machines could function as the “computers,” although I wonder if this couldn’t be done on a single computer (if necessary, could we do it with virtual machines?). Projecting the 2-D to 3-D data (that’s geographic projections, guys) is the mathematical stumbling block but most GIS software can handle it now. The specs state that the software accepts most graphics formats, but these are static .gifs, .jpegs, etc. Integrating the system with a GIS platform would allow the user to add/modify layers and create annotations on the fly (think of a sketch map, except rotating and 6 feet in diameter). I’ve simplified some of the details, but it’s doable.

Of course, this division of NOAA probably worked out a very nice GUI and, of course, they’ve managed the coordination of the projectors. The site mentions that they’ve developed an API and they adopted an Open-Source Software License so perhaps we will shortly be able to download the source code so we can create our own applications.

(The oblate spheroid is a geography reference. Planets tend not to be spheres. Most are oblate spheroids. That’s why in addition to projections, you also need to worry about things called datums too.)

coral reef bleaching on Google Earth

Saturday, April 8th, 2006

The US National Oceanic and Atmospheric Administration (NOAA) has made its satellite images and environmental data on coral bleaching available on Google Earth. Now you can watch the coral reefs disappear on your laptop!

ruin your day…

Friday, February 17th, 2006

This will do it:

Greenland’s glaciers are melting into the sea twice as fast as previously believed, the result of a warming trend that renders obsolete predictions of how quickly Earth’s oceans will rise over the next century, scientists said yesterday.

The new data come from satellite imagery and give fresh urgency to worries about the role of human activity in global warming. The Greenland data are mirrored by findings from Bolivia to the Himalayas, scientists said, noting that rising sea levels threaten widespread flooding and severe storm damage in low-lying areas worldwide.

(A summary of the article in Science is here.)

If this wasn’t depressing enough, Jim Hansen, the NASA scientist who’s been prevented from speaking out about dramatic acceleration of climate change, had to publish his article in a newspaper in the UK:

a few weeks ago, when I – a NASA climate scientist – tried to talk to the media about these issues following a lecture I had given calling for prompt reductions in the emission of greenhouse gases, the Nasa public affairs team – staffed by political appointees from the Bush administration – tried to stop me doing so.

climate predictions

Tuesday, February 14th, 2006

British Scientists are making use of various media to publicise and popularise their climate prediction project. Scientists have teamed up with the BBC online as well as BBC television to try to get global participation in a distributed computing program. This project should not only increase scientific knowledge of climate change, but also increase public awareness of issues…the new program is different from the old one (which has beeen running for two years) in that it represents ocean cycling as well as atmospheric cycling, allowing for more realistic predictions.

finding fish

Monday, February 13th, 2006

MIT researchers has developed a new way to find fish in the ocean. Using modified sonar, the device can map fish at much greater depths and distances than traditional techniques.

The NYTimes article says the device is a boon for conserving fish because scientists can use it to better understand the behaviour of shoals of fish. Let’s hope the technology is not so cheap that the big trawlers also can use it.

A movie of the modified sonar is here. Warning: it’s a BIIIG file.

Dueling models: the temperate forest edition

Sunday, February 12th, 2006

Creating mechanisms to capture carbon was one of the major topics of this past climate change conference. One way to do this is through forests: trees in forests capture, “sequester,” carbon dioxide by absorbing it as part of photosynthesis. In the Kyoto Protocol, countries can offset their greenhouse gas emissions by planting forests, so called ‘Kyoto forests’. There is strong incentive for countries that signed on to Kyoto to do afforestation, the planting of trees in areas where there previously were no trees, or reforestation, the planting of trees in areas where there used to be trees.

Instead of sequestering carbon, now it’s been shown that the expansion of forests in temperate climates might actually increase the emission of carbon dioxide. Why such a radical change in viewpoints? It may be a result of re-examining the assumptions of the computer simulations of climate change.

Johannes Feddema of the University of Kansas and six colleagues from the US National Centre for Atmospheric Research report in Science journal that they looked at changes in land use – the growth of cities, clearing of forests for agriculture, and draining of marshes – and their impact on climate change in the next 100 years. They confirmed something environmentalists have predicted for decades – the destruction of the Amazon forest would make the local climate 2C (4F) warmer because trees soak up carbon dioxide from the atmosphere, and burning them releases it. But then the scientists looked at temperate zones and found the opposite.

Simulations predicted the conversion of north American and European forests and grassland to agriculture would cool the region and counteract the effects of global warming by 25%-50%. This is because ripening corn and other staples would reflect more sunlight back into space, and release more moisture into the air, while dark forests would absorb sunlight and send thermometers soaring. Ken Caldeira and a Carnegie Institution team backed the finding in Geophysical Research Letters. “We were hoping to find that growing forests in the US would help slow global warming. But if we are not careful, growing forests could make global warming even worse.”

So is this model correct? Plenty of carbon models still show carbon sequestration occuring more uniformly across forest types. This latest model demonstrates that considerable uncertainty persists in understanding role of forests in lessening climate change and certainly calls into question the use of forestation to remediate climate changes.

Climate Change and eActivism

Sunday, January 22nd, 2006

Most NGOs use online tools for communication purposes, this is no different then any other organization. Why is the use of computer-mediated communication so important for climate change issues and NGOs? Because the problem is: Global? Complex? Requires clear communication? Or is it just because it’s different and considered cool?

Ice on the Internet

Tuesday, January 10th, 2006

Worried about reduction of the Earth’s cryosphere? At least you can see the coolest animation of it on the web. This video from NASA’s Goddard Space Flight Center is an amazing combination of geo-visualization, temporal modeling, and 3-D modeling. All in a single shot of cruising over Antarctica (replete with roving annotations) to settling on sections of South and North America to moving to the Arctic and finally on to Greenland. It’s also a seamless blend of very different models (e.g., movements of glaciers and changes in mountain snow cover). The site mentions the importance of continued collection of data. I hope that viewers get a sense of the enormous quantity of spatial data needed to produce this seven minute animation.

No GIS is mentioned, however. Sigh.

Wired reefs

Sunday, December 18th, 2005

The Australian government is looking to computing technology to curtail water-borne pollution, which is destroying the Great Barrier Reef. The government intends to wire the reef network with a network of sensors that will relay information on water quality. Wiring will start with the Davies Reef and will build on the weather station already at the reef. Reef-based sensors will initially measure salinity, humidity and light. Rivers that open onto the reefs will contain sensors that will measure non-point source pollutants such as fertilizers.

Wiring the reefs is not easy:

Creating a wireless sensor network is challenging. An added difficulty in this project is the deployment of sensors in a marine environment: saltwater is corrosive and tropical waters encourage the growth of biological life on surfaces.

Data from the sensors will be used as inputs to computer models to project impacts on the corals, fish and overall reef quality.

For other instances of wired habitats, see the post on wired woods.

GIS and archaeology

Monday, December 5th, 2005

Archaeology provides us with a historical timeline of human life and development that dates back over one hundred thousands years. The discipline is a means by which we can track changes in various aspects of human culture, making it a two-dimensional field of study, comprised of both a spatial and a temporal aspect. There has been increasing interest in integrating GIS, remote sensing and GPS into archaeology. These tools can be used for large-scale research and data processing, acting as a means to combine results of different archaeological studies into an integrated database.

One such way GIS is applicable to archaeology is in something called “aerial archaeology”. Aerial archaeology encompasses satellite imagery, whether it be from SPOT or GPS satellites, color aerial photography or high-resolution height data, that are then used to generate digital terrain models (DTM) of archaeological sites and monuments. With DTMs, GIS provides a form of landscape management through an easily accessible computer database, which allows for analytical purposes.

The initial stage of aerial archaeology involves digitizing. A scanner digitizes the surface of an artifact or monument in the form of x, y, and z co-ordinates. A connectivity list describes the relationship of the points to each other. Through computer aided design (CAD), the DTM of the archaeological site or object is created. After RE (reverse engineering), which is the process of acquiring point data from the surface of the artifact, the point co-ordinate data is then converted into a physical prototype using an RP (rapid prototyping) technique. The final digital 3-dimensional replication of the object or monument can then be accessed, altered, or analyzed with ease by archaeologists. Here’s an example of modelling artwork and archaeological forms.

This is one example of how GIS can be used as an interactive tool for modeling and analyzing archaeological information. Who knows, maybe in the future this will replace traditional archaeological methods.

Thanks to MP for the post.

For another instance of GIS and the social sciences and humanties, see the Electronic Cultural Atlas Initiative, a spatially catalogued digital library of cultural and historical resources.

Google base

Wednesday, November 16th, 2005

Google announces Google Base. Google Base enables content owners to easily make their information searchable online. Anyone, from large companies to website owners and individuals, can use it to submit their content in the form of data items. We’ll host the items and make them searchable for free.

As far as I can tell, here are the main features:

  1. You describe the items that you post with attributes, that is tags that describe or catalog the items. The tagged items will be searched by the Google search engine and will be more accessible to people looking for these sorts of items.
  2. Items can be online information, including images, video and sound but thay also can be “offline” information (competition with eBay and craigslist, anyone?).
  3. This might be useful to people who don’t want to design a whole web page or series of web pages and services to support the distribution of information about said items.
  4. Presumably this opens up your items to a much larger audience. Unlike searching through millions of web pages with unstandardized categories, people will more easily find you and your item. Of course, what happens when there are millions of items?
  5. It’s free. I assume that Google makes money off the banner ads.

The feature was announced on Google Blog. Google has a blog? I guess I shouldn’t be surprised.

I love this comment from slashdot:

Google to me seems like a new Catholicism. Everything consolidated under a monolithic central power with a mandate of “doing no evil”. They send missionaries in the form of Bots and Ad Words to uncharted territory seemingly to help netizens in the wild, while gathering statistical data about what large masses of people are doing where, when and why. With this they can build their own versions of everything. Your home (page) is nothing compared to their cathedral. Heathens flock to it and erode their old societies under Google (capital G).

I tried Google base and immediately found a link on virtual activism and on environmental nonprofit organizations.

Virtual worlds, virtual vacations

Sunday, October 30th, 2005

But is there room for virtual eco-tourism?

New satellite imaging reveals rainforest devastation

Saturday, October 22nd, 2005

New satellite imaging techniques have revealed that the Amazon rainforest is being destroyed twice as fast as previously thought.

Scientists have discovered that previous satellite photographs of the Amazon have missed a form of surreptitious logging that is equally destructive, but not as apparent from space.

Now a team of American and Brazilian specialists have for the first time been able to assess from space the damage done by “selective logging”, when one or two trees are removed leaving surrounding trees intact.

More on the imaging:

Scientists have been working for eight years to find a way of detecting the large-scale damage caused by selective logging. From this work emerged the Carnegie Landsat Analysis System (CLAS) which processes data from three Nasa satellites. The information is fed into a powerful supercomputer which can spot changing patterns within each image pixel.

“For example, the signals tell us how much green vegetation is in the canopy, how much dead material is on the forest floor and how much bare soil there is,” said Dr Asner [, head of the study]. “Extracting those data has been a Holy Grail of remote sensing. With CLAS, we’ve been able to obtain a spatial resolution of 98ft by 98ft for the Brazilian Amazon Basin. That’s huge.”

I don’t know whether to call this positive technological innovation or not, considering how depressing the findings are.

Click here and here for more info on the Stanford work.

Arctic ice melting at dramatic pace

Thursday, September 29th, 2005

Dramatic photos to back up earlier computer models.