On the Ice

Condition 2!

I experienced my first Condition 2 weather down here yesterday, 5 December. Technically, I wasn’t in Condition 2 weather, but I saw it. For those of you who don’t know what “Condition 2” is: we have different conditions to indicate how severe the weather is; it determines whether or not it is safe to conduct work and travel outside. Here is an overview*:

Condition 3:
Winds less than 48 knots (55 mph), and/or
Visibility greater than or equal to 1/4 mile, and/or
Wind chill temperature warmer than -75F.

Condition 2 (all must be sustained for at least one minute):
Winds 48 to 55 knots (55 to 63 mph), and/or
Visibility less than 1/4 mile, but greater than or equal to 100 feet, and/or
Wind chill between -75F and -100F

Condition 1 (all must be sustained for at least one minute):
Winds greater than 55 knots (63 mph), and/or
Visibility less than 100 feet, and/or
Wind chill colder than -100F

*For more details, see https://www.usap.gov/USAPgov/travelAndDeployment/documents/FieldManual-Chapt10Weather.pdf

Yesterday, the most likely cause of the Condition 2 weather was the blowing snow, decreasing the visibility. Because of this, the only locations that had Condition 2 weather were Pegasus Field and the road to Pegasus Field, both of which are on the ice field off of McMurdo. Here is a “during and after” comparison of what the ice field looked like during Condition 2 weather, and afterwards when it was condition 3:

View from McMurdo, looking towards Condition 2 weather on the ice at around 12:30 pm on 5 December

View from McMurdo, now with Condition 3 weather on the ice, at around 9:30 pm on 5 December

It is incredible how much the visibility can decrease by blowing snow. There was also snow falling in McMurdo, and presumably on the ice, which surely contributed to the lack of visibility on the ice.

As cool as it was to see Condition 2 weather, it is important to realize how unsafe it is. My roommate, Adam, works for the WISSARD (Whillans Ice Stream Subglacial Access Research Drilling) Project, which is concerned with drilling in the ice. They work out on the ice there near Pegasus Field (for now), and when they were driving back to McMurdo, the visibility was so poor that the driver lost sight of the road. They ended up getting stuck in the snow, leaving them no choice but to dig and push the vehicle out. Even on something so seemingly safe as a day-trip drive to the ice can become a hazard when Condition 2, or worse, weather sets in.

Posted in Uncategorized | Comments Off on Condition 2!

Comments are closed.