Beautiful Places – Guernsey

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A heady mix of stunning scenery and contemporary living make Guernsey an ideal place to relax. Inspiring walks along the cliff paths, rambles through the rural interior can be combined with lazy days on the island’s beautiful beaches. St Peter Port, the island’s capital, is a bustling harbor town with a tapestry of architectural styles that tell the story of the region’s changing fortunes. Here bistros, restaurants and boutiques jostle, while the harbor ferries make travel to the other Channel Islands (Jersey, Alderney, Sark etc) simple. Although Guernsey is geographically much closer to France than the UK, it is loyal to the British crown. This loyalty, can be traced back to Norman times when the Channel Islands first became part of the English realm, and forms the basis of the island’s constitution.

Beautiful Phenomenon – The Jet Stream

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Most of us think rarely about the jet stream and the impact it has on our lives but it has a huge influence on weather and climate and certainly on air travel. As the picture shows, from space it looks quite beautiful.   Here the Northern Hemisphere Jet Stream can be seen crossing Cape Breton Island in the Maritime Provinces of Eastern Canada. The Jet Stream is a narrow zone of high-speed winds typically found at altitudes of 4 to 8 miles (8-12 km) above the earth. They result from temperature contrasts between polar and tropical regions. The strongest Jet Stream winds are found in the winter when the contrast between polar and tropical regions is the greatest. Wind speeds can reach 90 to over 180 miles per hour (145 to over 290 km/h) from west to east. Jet Streams are found between latitudes 20? to near 55? north and south. During the winter months over the United States and southern Canada, the path taken by the Jet Stream can have a large influence on the weather conditions of this region. (Courtesy NASA)

Beautiful Disappering World – Sea Ice

Article by Michon Scott design by Robert Simmon

April 20, 2009

This Article is from the NASA Earth Observatory Website to which there is a link below

Sea ice is frozen seawater that floats on the ocean surface. It forms in both the Arctic and the Antarctic in each hemisphere’s winter, and it retreats, but does not completely disappear, in the summer.

Sea ice plays an important role in the climate and ecosystems of the Arctic and Antarctic. (Photograph ©2008 fruchtzwerg’s world.)

The Importance of Sea Ice

Sea ice has a profound influence on the polar physical environment, including ocean circulation, weather, and regional climate. As ice crystals form, they expel salt, which increases the salinity of the underlying ocean waters. This cold, salty water is dense, and it can sink deep to the ocean floor, where it flows back toward the equator. The sea ice layer also restricts wind and wave action near coastlines, lessening coastal erosion and protecting ice shelves. And sea ice creates an insulating cap across the ocean surface, which reduces evaporation and prevents heat loss to the atmosphere from the ocean surface. As a result, ice-covered areas are colder and drier than they would be without ice.

Sea ice also has a fundamental role in polar ecosystems. When sea ice melts in the summer, it releases nutrients into the water, which stimulate the growth of phytoplankton, which are the base of the marine food web. As the ice melts, it exposes ocean water to sunlight, spurring photosynthesis in phytoplankton.When ice freezes, the underlying water gets saltier and sinks, mixing the water column and bringing nutrients to the surface. The ice itself is habitat for animals such as seals, Arctic foxes, polar bears, and penguins.

Life thrives along the margins of sea ice. Melting and freezing enhance circulation, bringing nutrients to the surface. The nutrients nourish phytoplankton, which are the base of the ocean food web. All marine animals, including the magnificent killer whale, ultimately depend on phytoplankton. (Photograph courtesy Donald LeRoi, NOAA Southwest Fisheries Science Center, NSF Antarctic Photo Library.)

Sea ice’s influence on the Earth is not just regional; it’s global. The white surface of sea ice reflects far more sunlight back to space than ocean water does. (In scientific terms, ice has a high albedo.) Once sea ice begins to melt, a self-reinforcing cycle often begins. As more ice melts and exposes more dark water, the water absorbs more sunlight. The sun-warmed water then melts more ice. Over several years, this positive feedback cycle (the “ice-albedo feedback”) can influence global climate.

Sea ice plays many important roles in the Earth system, but influencing sea level is not one of them. Because it is already floating on the ocean surface, sea ice is already displacing its own weight. Melting sea ice won’t raise ocean level any more than melting ice cubes will cause a glass of iced tea to overflow.

The Sea Ice Life Cycle

When seawater begins to freeze, it forms tiny crystals just millimeters wide, called frazil. How the crystals coalesce into larger masses of ice depends on whether the seas are calm or rough. In calm seas, the crystals form thin sheets of ice, nilas, so smooth they have an oily or greasy appearance. These wafer-thin sheets of ice slide over each other forming rafts of thicker ice. In rough seas, ice crystals converge into slushy pancakes. These pancakes can slide over each other to form smooth rafts, or they can collide into each other, creating ridges on the surface and keels on the bottom.

(At left) Sea ice begins as thin sheets of smooth nilas in calm water (top) or disks of pancake ice in choppy water (2nd from top). Individual pieces pile up on top of one another to form rafts and eventually solidify (3rd from top). Over time, large sheets of ice collide, forming thick pressure ridges along the margins (bottom). (Nilas, pancake, and ice raft photographs courtesy Don Perovich, Cold Regions Research and Engineering Laboratory. Pressure ridge photograph courtesy Ted Scambos, National Snow and Ice Data Center.)

Some sea ice is fast ice that holds fast to a coastline or the sea floor, and some sea ice is pack ice that drifts with winds and currents. Because pack ice is dynamic, pieces of ice can collide and form much thicker ice. Leads—narrow, linear openings in the ice ranging in size from meters to kilometers—continually form and disappear.

Larger and more persistent openings, polynyas, are sustained by upwelling currents of warm water or steady winds that blow the sea ice away from a spot as quickly as it forms. Polynyas often occur along coastlines where offshore winds maintain their presence.

Fast ice is anchored to the shore or the sea bottom, while pack ice floats freely. As it drifts, leads continually open and close between ice floes. Persistent openings, polynyas, are maintained by strong winds or ocean currents. (NASA satellite image courtesy Jacques Descloitres, MODIS Rapid Response Team .)

As the water and air temperatures rise each summer, some sea ice melts. Because of differences in geography and climate, it’s normal for Antarctic sea ice to melt more completely in the summer than Arctic sea ice. Ice that escapes summer melting may last for years, often growing to a thickness of 2 to 4 meters (roughly 6.5 to 13 feet) or more in the Arctic.

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For ice to thicken, the ocean must lose heat to the atmosphere. But the ice insulates the ocean like a blanket. Eventually, the ice gets so thick that no more heat can escape. Once the ice reaches this thickness—3 to 4 meters (10 to 13 feet)—further thickening isn’t possible except through collisions and ridge-building.

Ice that survives the summer melt season is called multi-year ice. Multi-year ice increasingly loses salt and hardens each year it survives the summer melt. In contrast to multi-year ice, first-year ice—ice that has grown just since the previous summer—is thinner, saltier, and more prone to melt in the subsequent summer.

Sea Ice : Feature Articles.

Beautiful Places – Arnside and Silverdale, England

Arnside

The AONB’s intimate green and silver landscape rises from the shores of Morecambe Bay, with wide views over the Kent Estuary to the Lake District. Despite its small scale, the AONB shows a unique interweaving of contrasting countryside.

The area is characterised by small scale limestone hills rising to less than 200m in height, fine deciduous woodlands and valleys which form sheltered agricultural land. The inter-relationship of salt-marsh, limestone cliffs and reclaimed mosses (peat bogs), at or about sea level, contrast markedly with limestone pasture, rock outcrops and limestone pavements at a higher level. The distribution of copses and hedgerows and the pattern of limestone walls create a strong feeling of enclosure, and are important elements in the landscape.

The limestone geology, varied soil types and vegetation, added to a notably mild climate at this northerly latitude, makes this AONB extremely important as a diverse natural habitat. Unimproved pasture and the exposed limestone outcrops are rich in rare butterflies and flowers. Between the limestone hills there are drift deposits and estuarine silts and clays which, close to the estuaries, support nationally important lowland raised mires. Woodlands are a distinctive element in the landscape with significant areas of ancient semi-natural woodland.

Large areas are owned by the National Trust (www.nationaltrust.org.uk/main/)English Nature (www.english-nature.org.uk/) and the Royal Society for the Protection of Birds (www.rspb.org.uk/) (RSPB) as well as local wildlife trusts and conservation organisations. The reed and willow swamps of RSPB Leighton Moss (www.rspb.org.uk/reserves/guide/l/leightonmoss/) are a major breeding site for marshland birds which include bearded tits, marsh harrier and the rare bittern. The sands and salt-marshes of Morecambe Bay are internationally important for wading birds and wildfowl. Parts of the AONB are of recognised national and international importance for wildlife.

Farming is, in the main, livestock, with sheep being grazed on the higher rough pastures and cattle and sheep farmed on the reclaimed valley soils. Some active quarrying remains and a small portion of the AONB is commercial conifer plantation. Private land ownership is concentrated on two large estates. Arnside, Silverdale and Warton are the main centres of population. The AONB is a popular destination for quiet outdoor recreation, caravanning and day visits.

Visit the Arnside and Silverdale AONB website (www.arnsidesilverdaleaonb.org.uk/) for further information.

Content supplied by the National Association for Areas of Outstanding Natural Beauty