|Mount Erebus, Ross Island, Antarctica from above the clouds. |
Photo © Bruce Luyendyk
Saturday, June 21, 2014
We live in the lower part of the atmosphere called the troposphere where Global Warming is taking place. Above the troposphere is the stratosphere where the ozone hole develops over Antarctica in Southern Hemisphere Spring. Most of us have been near the top of the troposphere – that is where transcontinental jet aircraft fly – about 11 kilometers up (35,000 feet). Another fact – ozone (a molecule of three oxygen atoms - O3) in the stratosphere is good. It shields us from the Sun’s damaging ultraviolet radiation that causes skin cancer. Ozone in the troposphere where we live is bad – a health hazard and greenhouse gas. It is generated there by industrial activity.
So what’s happening and what’s the connection?
Monday, June 16, 2014
November 22, 1989
Excerpt from chapter 6.
Scene: In McMurdo at the NSF Chalet Bruce and Team are briefed by staff on field operations and our Put-In flight to Marie Byrd Land. They tell us we need to get trained on the field radios we will use to stay in contact with McMurdo. The Navy runs communications…]
|McMurdo Station, 1989. Photo © Bruce Luyendyk|
We met a burly but nerdy Navy NCO1 - the radioman - in his office. He took us to a small windowless room with radios stashed on metal shelves along the walls. We crowded around him. “You’re gettin’ two Southcom 130 field radios, one is backup,” he said, then pulled two off the shelves and put them on a table. About the size of a medium attaché case, olive drab, weighed 20 pounds each, had a distinct no-frills, rugged military look to them. I saw knobs with cryptic labels in front and several connectors in the back - looked complicated. We began to get a lecture so I took out my field notebook.
He didn’t pause as he told us we would use these to check in daily and report weather observations. We would learn how to do that with Mac Weather upstairs in this building, he grinned, maybe with the knowledge that we would have plenty to report from Marie Byrd Land. He handled the radio, showing us the knobs at front. “This here is a HF2 radio. I’m sure you guys know about that,” he said. No I don’t. “It’s got peak power of twenty watts,” he continued. Twenty watts? My car radio is more powerful than that. Doesn’t he know we will be a thousand miles away?
“So it’s single side band and can use upper or lower but we use only upper side band,” he continued. Why is that important? “Now you’re going to be on freqs in the megahertz range,” he said. I get that part; freqs is frequencies. He’s a radio geek, good. “Ones you care about are eight-niner-niner-seven for Mac Center aircraft and weather and eleven-five-five-three for field party check in, but that one doesn’t always work.” Huh? Then what?
“Batteries are charged with these solar panels,” he reached up, pulled those off the shelf. “Got to keep snow off ‘em to work,” he paused, “keep turnin’ them to face the Sun,” he told us. “Oh and batteries need to be warm so put the radio in a tent or better in your sleeping bag.” That radio and me won’t fit in my sleeping bag.
He reminded us that if they don’t hear from us for three days they would launch a SAR operation, Search and Rescue. Oh, and yeah, this year is a high sunspot cycle with magnetic storms and ionosphere trouble, so comms can be marginal now and then, he told us in a flat voice.
This is a lot of info. Who else paid attention? I glanced sideways at the rest of the team. No one took notes, but Steve nodded as the radioman spoke. Right, I thought, Steve was an engineer. We got this covered.
Turned out the next year camped in the Phillips Mountains we found our radio didn’t work, couldn’t receive or send, and the backup radio didn’t work either. Did both have shot batteries, frozen? We had three days to figure it out before SAR would fly out. They would find us alive of course, so we would be the butt of endless, merciless jokes in Mac town - better off dead.
With a voltmeter I had Steve found the antennae connector was shorted, bent by wind likely - we needed to re-solder it. He had a one-shot soldering iron but no solder. But the voltmeter had solder globs on its circuit board. So Steve melted solder off the voltmeter board and used that solder to repair the antennae connector - back in business in less than one day, no SAR.
1 Non Commissioned Officer
2 High Frequency
Monday, June 9, 2014
|Iceberg Ross Sea, Antarctica. Photo © Bruce Luyendyk|
A few weeks ago I posted about discoveries that showed dynamic collapse of marine-based parts of the West Antarctic Ice Sheet is underway (May 20, 2014). What I want to explore now is the current thinking of scientists on the role of Antarctica in sea level change this century.
It will come as no surprise that sea level is projected to rise from the influence of global warming. This is discussed in both the Intergovernmental Panel on Climate Change (IPCC) AR5 report (Assessment Report Five 2013) and the 2014 National Climate Assessment. What do these reports say about sea level change and Antarctica’s role – and do the reports address the dynamic collapse scenarios revealed by studies published in the last few months?