A conservative scenario is that by 2050 the observed trend will reduce summer minimum ice extent by 15%; this is an extrapolation of the satellite observations which are quite reliable and are not contradicted by climate model forecasts. For volume and thickness, a conservative estimate is obtained by extrapolating model forecasts that are not contradicted by sparse observations. By 2050. the end-of-summer volume can be expected to be down by about 40%, of which about 15% would be due to decreased extent and the remaining 25% would be seen in an end-of-summer thickness reduced by 25% to about 1.5 m.
Disappearance of the ice canopy will also eliminate the haven now provided to stationary submarines by ice keels. Active sonar detection of submarines, both by ASW sonars and by acoustic torpedoes, will become feasible.
In summary, melting of sea ice in the Arctic will turn into a conventional open-ocean ASW environment, with none of the advantages it now affords to an adversary strategic submarine.
- Naval Operations in an Ice-free Arctic Symposium, 2001 source
All four agencies that track Earth’s temperature (the Hadley Climate Research Unit in Britain, the NASA Goddard Institute for Space Studies in New York, the Christy group at the University of Alabama, and Remote Sensing Systems Inc in California) report that it cooled by about 0.7C in 2007. This is the fastest temperature change in the instrumental record and it puts us back where we were in 1930. If the temperature does not soon recover, we will have to conclude that global warming is over. ...It snowed in Baghdad for the first time in centuries, the winter in China was simply terrible and the extent of Antarctic sea ice in the austral winter was the greatest on record since James Cook discovered the place in 1770. source April, 2008
The USS Nautilus
(SSN-571) completed the first trans-Arctic voyage beneath the polar ice cap in 1958. The U.S. navy, for one, has since conducted under-ice operations routinely in strategic areas.
[P]rior to the USS Hawkbill's under-ice expedition
to the Arctic in 1999, the submarine's commanding officer required every officer on board to read chapter seven of Leary's book-a description of USS Sargo's hazardous 1960 Arctic cruise. source
During the Cold War, Western intelligence referred to Soviet SSBN operating areas in the Arctic and the Sea of Okhotsk as bastions
. ... Attack submarines of the USS Sturgeon
class (SSN 637) were well-suited for operating in these areas, being relatively quiet and having an under-ice capability. source
Based on research and development studies, performed in part by USS Memphis
(SSN691) which had been specifically modified during refit to serve as a technology test bed, several major improvements were made to the basic Los Angeles design. ... Furthermore, by strengthening the sail and moving the forward dive planes from the sail to the bow, the San Juan boats have a true 'under ice' capability. source
The first 39 submarines of the LOS ANGELES class had no under-ice capability
, and all had reduced depth capability, part of the cost for them to regain a few knots of speed. source
(SSN-21) class of 29 boats has been phased out for exorbitant cost. The budget for Virginias is being argued to this day.
Labels: Nautilus Hawkbill Sturgeon Memphis San Juan Los Angeles Seawolf Virginias climate change