Sunday, January 31, 2010

Scientists dive to explore unique bacterial community

There’s not much in the ice-covered lakes in the McMurdo Dry Valleys to interest anglers looking to land the big one. But for scientists who want to know more about some of Earth’s earliest organisms — and, by extension, to recognize what life may look like on other planets — those unique ecosystems represent a useful portal to the past.

Indeed, the lack of fish or other animals high on the food chain has allowed the microorganisms that live within the lakes to flourish unmolested, developing into communities thick enough to accumulate in layers on the lake bottoms.

“The cool part is that you can see microbial ecosystems on a landscape scale. There aren’t too many places around the world where you can do that,” noted Dale Andersen, with the SETI Institute’s Carl Sagan Center for the Study of Life in the Universe and principal investigator on a project to learn more about the microorganisms that dwell in Lake Joyce.

Lake Joyce — one of about a dozen perennially ice-crusted lakes spread throughout the valleys — is all the more unique in that it is one of only two known lakes in the region where the microbes have produced microbialites. These carbonate structures, composed of the same minerals that make up a coral reef, grow right in the layers of cyanobacteria, called microbial mats.

Andersen explained that his team, funded by NASA’s Exobiology Program and supported in the field by the National Science Foundation (NSF), is interested in learning more about the conditions that allow these organisms to grow and flourish in their dark and cold ecosystem. In turn, that information should shed light on the behavior of similar organisms billions of years ago.

“There are only a few places in the world where you can go to find living examples of those earlier ecosystems,” Andersen stressed. “The lakes in the Dry Valleys actually provide a very nice window back in time to compare notes, so to speak, with the fossil record.”

Andersen has made two previous trips to Lake Joyce, where he first discovered the carbonate structures growing from the microbial mat communities at about 20 meters depth. This will be the first extended study of the carbonate structures in a Dry Valleys lake, he said.

“The initial observations that we have are that the structures are pretty cool and there’s lots going on, but we don’t know much about them,” Andersen said.

“Each lake is totally different,” he added. “The external factors seem to be pushing the communities in different directions. That’s part of what makes these very unique ecosystems interesting to study — they’re essentially right next to one another and they’re each so very distinctive.”

Thursday, January 28, 2010

New wind farm in Antarctica to help power U.S., New Zealand research stations

Electrical power generation has gotten a different spin for two Antarctic research bases. U.S. and New Zealand officials held an opening ceremony on Jan. 16 for a three-turbine wind farm recently built on Ross Island. U.S. Ambassador David Huebner and New Zealand Foreign Minister Murray McCully officiated by video link with the site from New Zealand’s northern city of Auckland.

Live from Antarctica!
Check out the Antarctica New Zealand Wind Farm Web camera for a near real-time look at the turbines and the nearby sea ice.U.S. Secretary of State Hillary Clinton was also scheduled to attend the ceremony in Auckland, but was called away to help deal with the earthquake crisis in Haiti.

The wind farm will help power both McMurdo Station, the main research base for the U.S. Antarctic Program (USAP), and Antarctica New Zealand’s Scott Base. The two facilities, which support a range of polar research, are only about 2 miles apart and share logistical operations.
Each wind turbine can generate up to 330 kilowatts on a site called Crater Hill between McMurdo Station and Scott Base. Engineers estimate the wind farm will cut fuel consumption by about 240,000 gallons every year.

Wind-generated electricity will account for up to 15 percent of McMurdo Station’s annual electricity demand, but nearly all of Scott Base’s. Currently, both stations draw all of their electrical and heat demand from diesel generators and diesel-fired boilers.

Officials from the National Science Foundation, which manages the USAP, were expected to hold a separate ceremony to commemorate the green achievement on Jan. 20. NSF Director Arden Bement and NSF Office of Polar Programs Director Karl Erb were both to be in attendnace. Bement and Erb also attended a plaque dedication on the site of a former nuclear power plant that was shut down about 40 years ago — the one and only such facility built and operated in Antarctica.

Total cost of the wind turbine project was about $7.4 million, with New Zealand covering most of the cost as part of its contribution to the two countries’ shared logistics pool.USAP personnel upgraded roads and transported equipment to Crater Hill, as well as conducted site surveys and provided various supplies and equipment, to support the construction.If deemed successful, the wind farm may be expanded in other areas around Ross Island to further reduce McMurdo Station’s reliance on fossil fuels.

Thursday, January 21, 2010

Bugs: Victims of Climate Change

If it were up to Jessica Hellmann, insects such as butterflies and beetles would wield just as much conservation clout as traditional conservation icons, such as polar bears, tigers and dolphins.

"Animals such as polar bears, tigers and dolphins are tremendously important, but mostly because they help define how we think about our relationship with the natural world," says Hellmann. "But when it comes to the functioning of ecosystems, insects are where it's at."

Why are insects so ecologically important? "They carry diseases, they pollinate and they have economic impacts on crops and timber," says Hellmann, a biologist at the University of Notre Dame. In fact, almost 80 percent of the world's crop plants require pollination, and the annual value of insect-pollinated crops in the U.S. is about $20 billion. What's more, most of the multicellular living organisms on Earth are insects.

They are also particularly sensitive to climate change--as invertebrates, they can't regulate their own body temperatures--making them "great little thermometers," Hellmann adds.
On the road again
How will those "great little thermometers" respond when climate change makes their habitats too hot or too dry for them?
Research conducted by Hellmann and Shannon Pelini, one of Hellmann's doctoral students, indicates that global warming may affect a single insect species differently throughout its various life stages, and that global warming affects different insect species in different ways.

Most importantly, as climate change progresses, some insects may become trapped--like fish out of water--in habitats that can no longer support them. The insects may therefore go extinct or lose genetically important segments of their populations. But other species, and no one knows which ones yet, may be able to reach cooler climates by moving north on their own.

Will such mobile species be able to survive on the unfamiliar plants living in their new habitats? To help answer that question, Pelini conducted laboratory experiments that involve exposing caterpillars of two butterfly species to climates and plants that occur across their ranges, and then monitoring the growth and survival rates of these groups.

She will soon announce in the journal Proceedings of the National Academy of Sciences (PNAS) how populations of these two butterfly species that live at the edges of their ranges will be affected by climate change and the various factors that may limit or reduce their northward expansion.

Hellmann is currently following up on Pelini's research by surveying thousands of genes in the two butterfly species in order to identify the genes that are turned off or on by climate change. These studies are designed to reveal the genetic bases for the tolerance of some insect species to climate change and the intolerance of others.

Tuesday, January 19, 2010

Real hero: Farley Mowat

Born: 1921 Belleville, Ontario Canada

Why he’s an Environmental Star! While living in Saskatchewan, young Farley visited the Arctic and started his lifelong passion for the preservation of Canada’s wildlife. Farley is one of Canada’s most famous conservationists and storytellers.

Schooling: University of Toronto

Facts and Figures: Farley’s books have sold over 18 million copies worldwide in 24 languages. Owls in the Family is perhaps Farley’s most famous book. A story that many Canadians have read in school, it is a popular tale about a young boy, his pets and their adventures together and a great read!

Did you know?

Farley is the great-grand-nephew of Ontario premier Sir Oliver Mowat
At the age of 13, Mowat founded a nature newsletter called Nature Lore.

Most awesome thing about Farley Mowat:

He was inspired to write the 1963 book Never Cry Wolf after spending time living in the Arctic observing the lives of wolves. At the time people were concerned with the declining caribou populations and suspected that the wolves were eating the caribou. They decided that the best way to protect the caribou would be to kill some of the wolves. After months of observation Farley concluded that the opposite was true! The wolves actually strengthened the caribou tribe because the wolves mainly ate field mice and only ate old or sick caribou — killing off the weakest. Farley concluded that the hunters in the area were using the wolves as scapegoats for the decline of the caribous, when in fact they were the ones hunting and killing them.

Monday, January 18, 2010

About Deep Space Communications

One of the most important and predominant functions involved in the exploration of space is its communication system. This system is responsible for sending scientific data from spacecraft back to Earth. It also provides the capability of tracking the spacecraft and commanding it to take certain actions. Without an effective communications system a successful mission would not be possible.

The challenge of deep space communication has been the enormous range of distances that spacecraft have traveled in the past 50 years. Planetary spacecraft have reached distant planets tens of billions of miles from Earth, and have successfully performed their functions. The necessity of minimizing spacecraft mass presents a major challenge to communications system engineers, as engineers must consider the issues of providing power supply, antennae, and many other necessary devices and supporting elements for a communications system. Another important challenge is the extreme reliability required of the communications systems on the spacecraft. Once the spacecraft is launched, on-board failures can be repaired only by relying upon redundant and adaptive systems. Communication engineers must take into consideration such factors as system degradation, aging, and imperfect antenna positioning, as well as operations and data procedures.

In the past, spacecraft data return rates have been tens to hundreds of kilobits per second (kbps) and uplink command data rates have been limited to a few kbps. Recent missions such as MRO can transmit data to Earth at rates as high as 6 megabits per second. For more demanding missions in the near future, much higher data capabilities will be required.
DSN image

The Deep Space Network (DSN) operated for NASA by the Jet Propulsion Laboratory (JPL), provides deep space communications, tracking of spacecraft, and performs many scientific experiments. Because future space missions promise to explore the far reaches of the solar system and beyond, the DSN would need to expand its technological and communications capabilities to meet greater science data return rates and the requirements of advanced spacecraft. For example, by one estimate, the DSN might have to support over twice the missions in 2020 as it supported in 2005, and the data rate from each mission could average at least a factor of 10 higher.

The DSN consists of antenna arrays in 3 locations around the world; near Madrid, Spain; near Canberra, Australia; the Goldstone facility in California’s Mojave Desert, and the command center at JPL in California. These facilities, approximately 120 degrees apart on Earth, provide constant coverage for a mission at critical times. Each facility has a number of antennae some of which can be operated as an array, including at least two 34-meter arrays, and a giant 70-meter array in each location. Use of the arrays is scheduled well in advance for all interplanetary missions as their use is in high demand.

To enable future critical space exploration missions, new technology investments are needed so that future programs will continue to be successful and affordable (i.e. no specific program can afford to bear the burden of the technology development by itself). JPL sponsors internal development of several deep space communications efforts.

Sunday, January 10, 2010

Ozone hole drive rapid changes

One finding from recent years that received prominence in the SCAR report concerned the effects of the ozone hole on the Antarctic climate.

Unlike the coastal areas, particularly in West Antarctica, the interior of Antarctica has cooled slightly, according to polar researchers cited in the SCAR report. That’s because the ozone hole over the Southern Hemisphere has cooled the stratosphere, the layer of the atmosphere above the troposphere that people inhabit.

However, the ocean around the continent and regions to the north are warming. The temperature differential has caused atmospheric circulation to intensify around Antarctica, effectively shielding much of the continent from the intrusion of warmer air to the north.

But as the ozone hole heals, those westerly winds will ease, allowing warmer air to mix more easily into the Antarctic atmosphere. The SCAR report estimates a continent-wide temperature increase of 3 degrees Celsius by 2100.

“This is what has happened in the northern hemisphere. You have a relatively warm Arctic and a warm low- to mid-latitudes, and the westerlies have slowed down,” Mayewski said. “The big questions for the Antarctic are when it will happen and how fast will it happen.”

Mayewski said based on climate records, particularly from ice cores, that sudden shifts in position and strength of the westerlies have created many of the abrupt climate changes of the past.
Mayewski said: “The implicit but not explicit statement in my mind in this report is the fact that we could very well be headed for not a linear change in the westerlies, but an abrupt change in the westerlies,” he said. “If we experience a very abrupt weakening of the westerlies — we can show that it happened in the past — we could very well have accelerated levels of warming in Antarctica.”

A recent paper in the journal Geophysical Research Letters by Marco Tedesco at City College of New York and Andrew Monaghan at the National Center for Atmospheric Research in Boulder, Colo., suggested that a 30-year record low in Antarctic snowmelt during the 2008-09 austral summer was likely due to intensified westerlies and El NiƱo-Southern Oscillation (ENSO). ENSO is a periodic change in oceanic and atmospheric conditions in the tropical Pacific Ocean that has far-reaching effects on weather around the world.


Thursday, January 07, 2010

Researchers find similarities between Earth and Saturn's largest moon

Researchers using ground-based telescopes and space probes make amazing discoveries about the atmospheric cycle of Saturn’s largest moon, and find similarities to Earth. Our knowledge of Titan has improved considerably over the last five years. Before that, Saturn's largest satellite had only been hastily approached by a handful of space probes.

In 1980, the Voyager-1 spacecraft took advantage of a flyby to take a few mysterious, yet frustrating, close-ups of Titan's opaque, rusty atmosphere. Despite its color, Titan actually seemed to look a lot like the early Earth.

There was a general feeling of excitement and perplexity: what lay beneath this atmosphere? Could Titan support life? In July 2004, NASA's Cassini space probe entered Saturn's distant realm, this time to stay. The probe was designed right after Voyager's visit by a scientific community eager to unveil those new mysteries.

And unveil them it did. It has been hard to keep up with the flow of discoveries delivered from Titan to Earth since then. We now know that the 5,150-kilometer- (km, or 3,200-mile-) wide world has lakes and riverbeds. Earlier this year, even fog was discovered at Titan's South Pole.
Even more compelling is the fact that, just like similar features on Earth, all of those features are tightly related. Evaporated liquids create clouds that are carried around the planet by winds--and probably cause precipitation. This has never been seen on any other extraterrestrial body.

Moreover, Titan's atmospheric cycle is not a water cycle. It is instead an exotic climate of hydrocarbons that features methane and ethane. On Earth, those are gases, but the extremely cold temperature of Titan, around minus 290 degrees Fahrenheit (F, or minus 180 degrees Celcius), allows them to be liquid as well (and maybe even solid).


Tuesday, January 05, 2010

Green algae helps in Advancing Bio-hydrogen

Photosynthetic organisms offer a biological paradigm for the conversion of light energy into chemical forms. Some of these organisms are capable of transducing this energy directly into H2. The green alga Chlamydomonas reinhardtii is an example of one such organism that could play a major role in future commercial H2-production system. However, the complexity of the metabolism linked to H2-production pathways in this organism demands the development of a computational model by which to integrate and understand disparate observations over various mutations and environmental conditions.

The grand scientific challenge of creating a complete, in silico simulation of a living cell still faces daunting obstacles. Biomolecular science has proceeded by studying prototypical systems, with the understanding that the knowledge gained is transferable to other systems to some extent. However, for quantitative modeling of a single system, complete knowledge must be available for that particular system to achieve consistency—assuming transferability of knowledge from prototypical systems may lead to fundamental errors in model interpretation.

This project will exploit existing and newly generated knowledge to construct an in silico simulation of metabolism relating to H2 production in C. reinhardtii. It will provide a fundamental understanding of essential metabolic pathways in photosynthetic green algae and enable rational engineering and optimization of those pathways. It will also serve a broader community by providing information critical to understanding other hydrogen metabolizing and fermentative organisms of interest in renewable energy research.

The Department of Energy's mission is to advance the national, economic and energy security of the United States. Within the Genomics:GTL program, systems biology has been identified as playing a key role in meeting the Department’s mission. Furthermore, the “hydrogen economy” has been established as an important component in a multi-faceted strategy for energy independence and renewability.