Archive

Posts Tagged ‘Environment’

Space Weather Warnings for Earth & Forecasts for Exoplanets

March 29, 2012 Leave a comment

The UK Met Office’s weather and climate model is being adapted to help understand space weather at Earth and the atmospheres of planets orbiting other stars. Two teams of scientists will present their work at the National Astronomy Meeting in Manchester.

The Met Office plans to expand its services to provide operational space weather forecasts for the UK. It is pooling skills with the UK’s space weather research community to extend its ‘Unified Model’ upwards to include the Earth’s thermosphere, a region about 90-600km above the Earth surface. The impact of space weather events is very commonly seen in this region.

“Space weather can affect the aviation and power industries, as well as a whole range of activities that rely on GPS timing and positioning, radio communication or satellite-based observations,” said the Met Office’s Dr David Jackson, who will present the project on Friday 30th March.

“To develop a more accurate and useful advanced-warning system for space weather, we need to develop a system of interconnected models that describe the whole domain – the conditions on the Sun, interplanetary space, the layers of the Earth’s atmosphere, all the way down to the Earth’s surface. The more accurate we can be in representing interactions between the lower atmosphere and thermosphere, the more we can enhance thermospheric forecasts, and thus improve space weather forecast products for users,” Jackson continued.

Full Story: http://www.jodrellbank.manchester.ac.uk/meetings/nam2012/pressreleases/nam13.html

Solar ‘Climate Change’ Could Cause Rougher Space Weather

March 29, 2012 1 comment

Recent research shows that the space age has coincided with a period of unusually high solar activity, called a grand maximum. Isotopes in ice sheets and tree rings tell us that this grand solar maximum is one of 24 during the last 9300 years and suggest the high levels of solar magnetic field seen over the space age will reduce in future. This decline will cause a reduction in sunspot numbers and explosive solar events, but those events that do take place could be more damaging. Graduate student Luke Barnard of the University of Reading will present new results on ‘solar climate change’ in his paper at the National Astronomy Meeting in Manchester.

The level of radiation in the space environment is of great interest to scientists and engineers as it poses various threats to man-made systems including damage to electronics on satellites. It can also be a health hazard to astronauts and to a lesser extent the crew of high-altitude aircraft.

The main sources of radiation are galactic cosmic rays (GCRs), which are a continuous flow of highly energetic particles from outside our solar system and solar energetic particles (SEPs), which are accelerated to high energies in short bursts by explosive events on the sun. The amount of radiation in the near-Earth environment from these two sources is partly controlled in a complicated way by the strength of the Sun’s magnetic field.

There are theoretical predictions supported by observational evidence that a decline in the average strength of the Sun’s magnetic field would lead to an increase in the amount of GCRs reaching near-Earth space. Furthermore there are predictions that, although a decline in solar activity would mean less frequent bursts of SEPs, the bursts that do occur would be larger and more harmful.

Full Story: http://www.jodrellbank.manchester.ac.uk/meetings/nam2012/pressreleases/nam12.html

Storms From the Sun

March 12, 2012 Leave a comment

Space weather starts at the sun. It begins with an eruption such as a huge burst of light and radiation called a solar flare or a gigantic cloud of solar material called a coronal mass ejection (CME). But the effects of those eruptions happen at Earth, or at least near-Earth space. Scientists monitor several kinds of space “weather” events — geomagnetic storms, solar radiation storms, and radio blackouts – all caused by these immense explosions on the sun.

One of the most common forms of space weather, a geomagnetic storm refers to any time Earth’s magnetic environment, the magnetosphere, undergoes sudden and repeated change. This is a time when magnetic fields continually re-align and energy dances quickly from one area to another.

Geomagnetic storms occur when certain types of CMEs connect up with the outside of the magnetosphere for an extended period of time. The solar material in a CME travels with its own set of magnetic fields. If the fields point northward, they align with the magnetosphere’s own fields and the energy and particles simply slide around Earth, causing little change. But if the magnetic fields point southward, in the opposite direction of Earth’s fields, the effects can be dramatic. The sun’s magnetic fields peel back the outermost layers of Earth’s fields changing the whole shape of the magnetosphere. This is the initial phase of a geomagnetic storm.

Full Story: http://www.nasa.gov/mission_pages/sunearth/news/storms-on-sun.html

NASA Mission Takes Stock of Earth’s Melting Land Ice

February 9, 2012 Leave a comment

In the first comprehensive satellite study of its kind, a University of Colorado at Boulder-led team used NASA data to calculate how much Earth’s melting land ice is adding to global sea level rise.

Using satellite measurements from the NASA/German Aerospace Center Gravity Recovery and Climate Experiment (GRACE), the researchers measured ice loss in all of Earth’s land ice between 2003 and 2010, with particular emphasis on glaciers and ice caps outside of Greenland and Antarctica.

The total global ice mass lost from Greenland, Antarctica and Earth’s glaciers and ice caps during the study period was about 4.3 trillion tons (1,000 cubic miles), adding about 0.5 inches (12 millimeters) to global sea level. That’s enough ice to cover the United States 1.5 feet (0.5 meters) deep.

Full Story: http://www.nasa.gov/home/hqnews/2012/feb/HQ_12-048_GRACE_Land_Ice_Study.html

New Ohio Park Protects Nighttime Environment

August 24, 2011 Leave a comment

An overcast sky in Geauga County, Ohio, did not dampen the enthusiasm of the 1,500 people attending Observatory Park’s dedication on 20 August, when it announced its full status as an International Dark Sky Park (IDSPark). The new park is the latest member of the growing IDSPlaces program, the flagship of the International Dark-Sky Association’s ongoing efforts to promote stewardship of the night sky.

Full Story: http://bit.ly/nDotyn