Thursday, January 22, 2009

Hazards Of Severe Space Weather Revealed

Hazards Of Severe Space Weather Revealed

ScienceDaily (Jan. 12, 2009) — A NASA-funded study describes how extreme solar eruptions could have severe consequences for communications, power grids and other technology on Earth.

The National Academy of Sciences in Washington conducted the study.

The resulting report provides some of the first clear economic data that effectively quantifies today's risk of extreme conditions in space driven by magnetic activity on the sun and disturbances in the near-Earth environment. Instances of extreme space weather are rare and are categorized with other natural hazards that have a low frequency but high consequences.

"Obviously, the sun is Earth's life blood," said Richard Fisher, director of the Heliophysics division at NASA Headquarters in Washington.

"To mitigate possible public safety issues, it is vital that we better understand extreme space weather events caused by the sun's activity."

Besides emitting a continuous stream of plasma called the solar wind, the sun periodically releases billions of tons of matter called coronal mass ejections.

These immense clouds of material, when directed toward Earth, can cause large magnetic storms in the magnetosphere and upper atmosphere. Such space weather can affect the performance and reliability of space-borne and ground-based technological systems.

Space weather can produce solar storm electromagnetic fields that induce extreme currents in wires, disrupting power lines, causing wide-spread blackouts and affecting communication cables that support the Internet. Severe space weather also produces solar energetic particles and the dislocation of the Earth's radiation belts, which can damage satellites used for commercial communications, global positioning and weather forecasting. Space weather has been recognized as causing problems with new technology since the invention of the telegraph in the 19th century.

A catastrophic failure of commercial and government infrastructure in space and on the ground can be mitigated through raising public awareness, improving vulnerable infrastructure and developing advanced forecasting capabilities. Without preventive actions or plans, the trend of increased dependency on modern space-weather sensitive assets could make society more vulnerable in the future.

NASA requested the study to assess the potential damage from significant space weather during the next 20 years. National and international experts from industry, government and academia participated in the study. The report documents the possibility of a space weather event that has societal effects and causes damage similar to natural disasters on Earth.

"From a public policy perspective, it is quite significant that we have begun the extremely challenging task of assessing space weather impacts in a quantitative way," said Daniel Baker, professor and director of the Laboratory for Atmospheric and Space Physics at the University of Colorado in Boulder. Baker chaired the panel that prepared the report.

"Whether it is terrestrial catastrophes or extreme space weather incidents, the results can be devastating to modern societies that depend in a myriad of ways on advanced technological systems," said Baker. "We were delighted that NASA helped support bringing together dozens of world experts from industry and government to share their experiences and begin planning of improved public policy strategies."

The sun is currently near the minimum of its 11-year activity cycle. It is expected that solar storms will increase in frequency and intensity toward the next solar maximum, expected to occur around 2012.

The Heliophysics Division of NASA's Science Mission Directorate in Washington provided funding for the study. The division seeks to understand the sun, its solar processes and the interaction of solar plasma and radiation with Earth, other planets and the universe.

Understanding the connections between the sun and its planets will allow better prediction on the impacts of solar activity on humans, technological systems and even the presence of life itself in the universe.

The National Academies are chartered by Congress to provide independent technical and scientific advice to the federal government.

For images related to the study and more information about the Heliophysics Division, visit: http://nasascience.nasa.gov/heliophysics

To view the National Academy of Sciences' complete report, visit: http://www.nap.edu/catalog/12507.html

WEATHER NOTE

Satellites Used To Measure Inland Floods

ScienceDaily (Dec. 23, 2008) — Satellites that were designed to measure sea level over the world's oceans can serve a valuable purpose over land, a new study has found. Researchers used NASA's TOPEX/Poseidon satellite and the European Space Agency's ENVISAT satellite to measure the height and extent of flooding in North America, South America, and Asia.

The study shows that satellites can supplement the measurements that the United States Geological Survey (USGS) gathers from flood gauges on the ground -- at little or no cost, said C.K. Shum, professor of earth sciences at Ohio State University.

"After a flood, we can look back at the satellite data to pinpoint when the flood began, and find out how far the flood waters extended, which is really important for flood modeling," he said.

Satellites such as TOPEX/Poseidon measure the height of land or water by bouncing radio signals off of surfaces and measuring how long the signals take to return.

Rough surfaces scatter some of the signal in other directions, and cause errors in a satellite's on board tracking system. This often happens over land. Scientists use "re-tracking" software to fix the errors, and make the satellite's measurements more precise.

That's what the Ohio State software does -- it re-tracks the satellite data, but in a way that enables detailed measurements of water on land.

The key to the software is an algorithm that can tell the difference between water and snow cover. Ohio State postdoctoral researcher Hyongki Lee developed the algorithm and graduate student Manman Zhang applied the algorithm for her doctoral thesis.

Zhang presented the work in a poster session at the American Geophysical Union meeting in San Francisco.

Shum, Zhang, and their colleagues used the software to process TOPEX/Poseidon data from the 1997 Red River flood in the upper Midwest of the United States, an area with abundant farmland and wetlands. They detected flooded regions within four river basins: the Red River Basin in North Dakota and Minnesota; the Missouri River Basin in North Dakota and South Dakota; and the Minnesota River Basin and the Mississippi River Basin, both in Minnesota and Iowa.

The flood happened in April of that year, as winter snows began to melt. Zhang's algorithm differentiated between the scattered radar signal produced by water and by areas still covered by snow. As the floodwaters began to move down the Red River, the satellite measurements provided estimates of flood levels.

After re-tracking, the satellite data agreed with USGS ground measurements taken at the time. For example, the software determined that flood waters in Grand Forks, North Dakota, rose 20 feet (6 meters), which matched data recorded from flood gauges there.

The researchers did the same for the June 2008 Iowa City flood that killed three people and damaged 2 million acres of farmland. They found that they could track the ebb and flow of that flood over a scale of several hours. For that part of the study, they worked with Carrie Huitger, a USGS hydrologist who supplied the flood gauge data. They performed similar studies with TOPEX/Poseidon data for a flood in the Amazon River Basin, and with ENVISAT data for a flood in southwestern Taiwan -- both with similar results.

The satellites can't be used to forecast a flood because the data isn't processed very quickly and the spatial coverage of the satellite measurements is limited, Shum explained. Even preliminary processing takes hours. But after a flood, such data can add to data collected on the ground, to help scientists better understand how floods happen.

Next, the researchers want to automate the software so that it can build an archive of flood data. Since the satellites are already in orbit collecting the data, there would be little cost beyond building the database and enabling scientists to access it.

In the future, a new satellite may enable more extensive and detailed measurements. Ohio State scientists lead an international team that has proposed the Surface Water Ocean Topography (SWOT) mission. The SWOT satellite will feature dual antennas that will gather high-resolution data over a much wider surface of the earth than is possible with today's satellites.

Collaborators on this project include Doug Alsdorf, associate professor of earth sciences, and Frank Schwartz, professor and Ohio Eminent Scholar in Hydrogeology.

This work was funded by the National Science Foundation and NASA.

Hail tornado severe storms lightning video Australia



MARITIME NOTE

Thousands urge rescue boat return

The crew of a Devon rescue boat is sending out its own SOS to get its vessel reinstated. A petition of 5,000 signatures is being handed in to parliament on Wednesday, saying lives are being put at risk.

The story made headlines last summer when the crew used the boat to rescue a teenage girl at Hope Cove.

The Maritime and Coastguard Agency (MCA), which had warned the crew that the boat was unsafe, impounded it. The MCA is due to hold talks on the issue.

The MCA later brought the boat back, with a restriction that it could be used within a certain distance from the beach in the South Hams area of Devon.

But two months ago the boat was locked away again, this time until a consultation was carried out.

The crew has said the boat is safe and fears lives are being put at risk.
MP Anthony Steen said: "The rescue boat had been successfully operated by four men who were able to launch the boat at a moment's notice in the event of an emergency since they worked locally.

"Now a large stretch of the south Devon coastline is suddenly without adequate sea rescue coverage."

The MCA said Hope Cove was covered by the nearby Salcombe lifeboat.
It said in a statement: "We will be consulting with stakeholders soon to discuss beach safety provision in the South Hams."

FROM HOLLAND AND KNIGHT

Singapore – comments sought re draft amendments to MARPOL Annex I The Singapore Maritime and Port Authority (MPA) issued a circular stating that it is seeking comments from owners, operators, masters, and others regarding draft interim guidelines and draft amendments to MARPOL Annex I adopted by the recent session of the IMO Marine Environment Protection Committee (MEPC). The draft documents relate to: (1) the method of calculation of the energy efficiency design index for new ships; (2) the Supplement to the IOPP Certificate; (3) prevention of pollution during transfer of oil cargo between oil tankers at sea; (4) amendments to Regulations 1, 12, 13, 17, and 38; (5) the IOPP Certificate; and (6) the Oil Record Book. The draft amendments are expected to be adopted at the next session of the MEPC, scheduled for July 2009. Shipping Circular No. 5 of 2009 (1/6/09).

UK – report on container ship-fishing vessel collision The UK Marine Accident Investigation Branch (MAIB) issued the summary of its preliminary examination of a collision between a container ship and a fishing vessel that occurred in good weather off Lizard Point on 18 September 2008. Visibility from the bridge of the container ship was impaired. Neither vessel was maintaining a good lookout or making proper use of their radar. (1/6/09).

UK – contract awarded for MSC NAPOLI wreck removal The UK Maritime and Coastguard Agency (MCA) issued a press notice stating that a contract has been awarded for removal of the stern section of the wreck of the MSC NAPOLI. The scrap is to be delivered to a recovery facility in the Netherlands. (1/6/09).

RS

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