Landsat 5 Satellite Helps Emergency Managers Fight Largest Fire in Arizona History

The largest fire in the history of the state of Arizona continues to burn and emergency managers and responders are using satellite data from a variety of instruments to plan their firefighting containment strategies and mitigation efforts once the fires are out.

The Landsat 5 satellite captured images of the Wallow North and Horseshoe 2 fires burning in eastern Arizona on June 15, 2011 at 19:54:23 Zulu (3:54 p.m. EDT). Both images are false-colored to allow ease of identification of various objects that will help firefighters and emergency managers. In the images burn scars appear in red and ongoing fire in bright red. Vegetation is colored green, smoke is colored blue and bare ground is tan-colored. The Landsat 5 image is a false color image with a 7, 4, 2 band combination.

The Wallow fire began May 29, 2011 in the Bear Wallow Wilderness area located in eastern Arizona. High winds and low humidity meant that by June 14, 2011 the Wallow Fire became Arizona’s largest wildfire to date with over 487,016 acres burned. On the morning of June 16 the fire is now 29 percent contained, according to Inciweb. Inciweb, the "Incident Information System" website, (www.inciweb.org) is an interagency all-risk incident information management system.

The National Weather Service has posted a Red Flag Warning for June 16 and 17. The warning forecasts strong winds from the southwest with gusts to between 35 and 45 mph.

Inciweb reported that the Horseshoe 2 Fire began on May 8 in Horseshoe Canyon on the Douglas Ranger District of the Coronado National Forest, located in southeast Arizona. The Chiricahua National Monument in the northern area of the fire was closed on June 9 and remains closed. As of June 16, 184,198 acres had burned, and the fire is reported as 60 percent contained.

The Landsat series of satellites is used by emergency managers to acquire a range of imagery and data, from floods to fires. Landsat has also recently provided images of the flooding of the Mississippi River.

The Landsat Program is a series of Earth-observing satellite missions jointly managed by NASA and the U.S. Geological Survey. Landsat satellites have been consistently gathering data about our planet since 1972. They continue to improve and expand this unparalleled record of Earth’s changing landscapes, for the benefit of all. The next Landsat satellite is scheduled to launch in December 2012.

Related Links:

Landsat at USGS
NASA's Landsat website
Landsat's 2012 launch website

Rob Gutro
NASA Goddard Space Flight Center

Zeitgeist: Addendum

Hagamos conciencia compañeros.

Solar fuel

Biologists discover how yeast cells reverse aging The gene they found can double yeast lifespan when turned on late in life.

A whole yeast (Saccharomyces cerevisiae) cell viewed by X-ray microscopy. Inside, the nucleus and a large vacuole (red) are visible.
Image: NIH

Human cells have a finite lifespan: They can only divide a certain number of times before they die. However, that lifespan is reset when reproductive cells are formed, which is why the children of a 20-year-old man have the same life expectancy as those of an 80-year-old man.

How that resetting occurs in human cells is not known, but MIT biologists have now found a gene that appears to control this process in yeast. Furthermore, by turning on that gene in aged yeast cells, they were able to double their usual lifespan.


If the human cell lifespan is controlled in a similar way, it could offer a new approach to rejuvenating human cells or creating pluripotent stem cells, says Angelika Amon, professor of biology and senior author of a paper describing the work in the June 24 issue of the journal Science.


“If we can identify which genes reverse aging, we can start engineering ways to express them in normal cells,” says Amon, who is also a member of the David H. Koch Institute for Integrative Cancer Research. Lead author of the paper is Koch Institute postdoc Elçin Ünal.


Rejuvenation


Scientists already knew that aged yeast cells look different from younger cells. (Yeast have a normal lifespan of about 30 cell divisions.) Those age-related changes include accumulation of extra pieces of DNA, clumping of cellular proteins and abnormal structures of the nucleolus (a cluster of proteins and nucleic acids found in the cell nucleus that produce all other proteins in the cell).


However, they weren’t sure which of these physical markers were actually important to the aging process. “Nobody really knows what aging is,” Amon says. “We know all these things happen, but we don’t know what will eventually kill a cell or make it sick.”


When yeast cells reproduce, they undergo a special type of cell division called meiosis, which produces spores. The MIT team found that the signs of cellular aging disappear at the very end of meiosis. “There’s a true rejuvenation going on,” Amon says.


The researchers discovered that a gene called NDT80 is activated at the same time that the rejuvenation occurs. When they turned on this gene in aged cells that were not reproducing, the cells lived twice as long as normal.


“It took an old cell and made it young again,” Amon says.


In aged cells with activated NDT80, the nucleolar damage was the only age-related change that disappeared. That suggests that nucleolar changes are the primary force behind the aging process, Amon says.


The next challenge, says Daniel Gottschling, a member of the Fred Hutchinson Cancer Research Center in Seattle, will be to figure out the cellular mechanisms driving those changes. “Something is going on that we don’t know about,” says Gottschling, who was not involved in this research. “It opens up some new biology, in terms of how lifespan is being reset.”


The protein produced by the NDT80 gene is a transcription factor, meaning that it activates other genes. The MIT researchers are now looking for the genes targeted by NDT80, which likely carry out the rejuvenation process.


Amon and her colleagues are also planning to study NDT80’s effects in the worm C. elegans, and may also investigate the effects of the analogous gene in mice, p63. Humans also have the p63 gene, a close relative of the cancer-protective gene p53 found in the cells that make sperm and eggs. 

The price of fresh air How costly are the health damages from air pollution in China?

Ozone concentration levels in China (1x1 degree grid cell), 2005.
Image: Lamsal et al., 

China has experienced unprecedented development over the past three decades, but this growth has come at a substantial cost to the country’s environment and public health. China is notorious for extremely high levels of air pollution. As the country faces continuous environmental challenges that mirror its continuing development, there is a need to measure the health impacts of air pollution.

A recent study released by the MIT Joint Program on the Science and Policy of Global Change quantifies the damage to the Chinese economy caused by a lack of air-quality control measures between 1975 and 2005. Not surprisingly, the MIT researchers found that air pollutants produced a substantial socio-economic cost to China over the past three decades.

What makes this study unique is that researchers looked at long-term economic impacts that arise from health damages, and how pollution-induced morbidity and mortality cases may have had ripple effects on the Chinese economy beyond the time period when those cases actually occurred. This method creates a comprehensive picture of the cumulative impacts of air pollution on a dynamic, fast-developing country.

“This study represents a more accurate picture than previous studies of the air-pollution damages associated with rapid economic development in China,” says Noelle Selin, an assistant professor of engineering systems in MIT’s Engineering Systems Division, with a joint appointment in atmospheric chemistry in the Department of Earth, Atmospheric and Planetary Sciences. “A major advantage of this study over previous work is that it links state-of-the-art atmospheric modeling tools with a comprehensive global economic model incorporating health and economic damages from pollution.”

To observe how changes in pollutants, and their associated health impacts, have historically affected the Chinese economy, the MIT researchers modeled the number of cases of health incidences caused by air pollution — such as restricted-activity days, respiratory hospital admissions and asthma attacks, to name a few examples — given a pollution level and the number of people exposed. Then the model calculated the summed costs of these incidences — i.e., payments for health services and medicine, loss of labor and productivity from time off work, loss of leisure time needed for healing — to estimate the total change in available labor supply.

The study focused on two major air pollutants: particulate matter and ozone. Levels of particulate matter, which causes respiratory and cardiovascular diseases and accounts for a large fraction of damage to human health, are extremely high in China. In the 1980s, particulate matter concentrations were at least 10-16 times higher than the World Health Organization’s annual guidelines. Even in 2005, after significant improvements in Chinese air quality, concentrations were still about five times higher than the guidelines.

China has only recently begun monitoring levels of the second air pollutant, ozone. Chinese ozone data does not exist between 1970 and 2005, the period considered in this study. In fact, most air pollution studies of China omit the pollutant completely due to lack of data. However, the MIT study incorporates historical ozone levels over the past three decades as simulated by GEOS-Chem (a chemical transport model) and MIT’s Integrated Global Systems Model, thus significantly improving on previous studies of pollution damage.

The researchers found that, although the magnitude of air pollution in China decreased over the three decades, damages associated with the pollutants created a substantial burden on the Chinese economy. “The results clearly indicate that ozone and particulate matter have substantially impacted the Chinese economy over the past 30 years,” Selin says.

When comparing historical pollution levels and the associated impacts with a counterfactual scenario in which pollutants were restricted to background levels, or the best attainable air quality standards, China experienced an increasing loss in welfare — from $22 billion lost in 1975 to $122 billion lost in 2005 — from pollution-related health impacts.

There are two main reasons for the increasing loss in welfare, despite reduced levels of pollution between 1975 and 2005. First, rapid urbanization and growth increased the number of people exposed. Second, productivity of labor increases over time so that costs from lost labor are higher in recent times than in periods in the past. These factors outweigh the small improvements in air quality.

If a modest, feasible level of air-pollution control measures had been implemented over the time period, China would have reaped an increasing benefit in welfare — potentially growing from $18 billion gained in 1975 to $80 billion in 2005.

Similar studies conducted by the World Bank have found that air pollution in China caused damages equal to 4-5 percent of the Chinese GDP between 1995 and 2005. However, these estimates are based on static measurements that do not measure the cumulative, long-term impacts of health damages. The MIT study found a significantly higher level of damage, equaling 6-9 percent of the Chinese GDP. The dynamic, cumulative method used in the MIT study may be particularly applicable to developing countries that are experiencing rapid growth.

The MIT study looked at the benefits of air-quality controls on health damages in China, but did not calculate the costs of implementing such policies. Future work will focus on the costs of pollution controls so that a complete cost-benefit analysis can be developed.