This isn’t because the cosmic rays are affecting the atmosphere, but rather the other way round. If the stratosphere heats up, its density is reduced and fewer inbound cosmic particles collide with air molecules. In particular, incoming mesons are destroyed when they hit air – but if they don’t, they decay into muons.
Muons can be detected, provided the detector apparatus is well shielded from extraneous interference – in this case, by putting it in a disused iron mine half a mile underground in Minnesota. The NCAS boffins, analysing four years of records, found that an increased rainfall of ex-meson muons could be correlated in retrospect with sudden strato-heatwaves and their associated effects.
“Now we can potentially use records of cosmic-ray data dating back 50 years to give us a pretty accurate idea of what was happening to the temperature in the stratosphere over this time,” says Dr Scott Osprey of NCAS.
The north polar cap is a dome of layered, icy materials, similar to the large ice caps in Greenland and Antarctica, consisting of layered deposits, with mostly ice and a small amount of dust. Combined, the north and south polar ice caps are believed to hold the equivalent of two to three million cubic kilometers (0.47-0.72 million cu. miles) of ice, making it roughly 100 times more than the total volume of North America’s Great Lakes, which is 22,684 cu. kms (5,439 miles).
The footprint for the proposed project covers 24 square miles, 15.8 miles from the island town of Nantucket. The project envisions 130 horizontal-axis wind turbines, each having a hub height of 440 feet higher than the Statue of Liberty, which stands at 305 feet. The blade diameter is 364 feet. The turbines would be sited between 4-11 miles offshore depending on the shoreline. This is enough to meet the needs of 420,000 homes.
Currently 45% of the Cape region’s electricity comes from the nearby Canal Power Plant in Sandwich, which burns bunker oil and natural gas. The Cape Wind proposal is relatively unique in that it would directly offset petroleum usage unlike most of the country where electrical power generation from oil is rare and coal power is more common.
AeroCopter’s MTR vehicle has a single turbine driving a ducted fan pusher propeller and the electromagnetically driven 8.2m (27ft)-diameter ring that encircles the fuselage. Lift is generated by the rotor blades of the ring, which has counter-rotating upper and lower halves. A driveshaft linking the ring to the turbine uses permanent magnets to turn the ring, which has many more magnets located at short intervals around its circumference. Once at 1,000ft (305m) altitude the ring is tilted through 87° and locked in place.