Sept. 25th, 2002—Preparation for Expedition

Brian Grigsby

Helen Lake, Lassen Park, CA.

Most of the ascent team met on the shore of Lake Helen at Lassen for altitude free diving training in preparation for the expedition. The reasons for using this lake were simple ones: (1) it is a high altitude lake with cold water, at an altitude of about 8000 feet, (2) some conditions would be very similar to those experienced once in Chile at the Lagunas, (3) this would allow some of the team members to gain some experience in safety procedures, free diving, and testing blood-oxygen saturation levels.

The team members for this practice were: Dr. Nathalie Cabrol, Dr. Edmond Grin, Andy Hock and Marcus Murbach.

This was my first time meeting Andy Hock and Marcus Murbach. Andy had come up from UCLA and Marcus had flown in from the east coast where he had just finished some experiments testing the atmosphere re-entry capabilities of certain space systems. The team began by doing some initial blood-oxygen saturation levels. This is done to see the affects altitude has on the amount of oxygen in a person’s blood. The higher you go, the less available oxygen there is, and less of it can be picked up by your blood.

After these brief tests, Andy, Nathalie, and Marcus begin to don their wet-suits to adjust the weight needed for comfortable free diving that will take place once we are there.

Transportation of equipment will be critical once we begin the ascent up Licancabur because we want to minimize our weight as much as possible, so this testing is crucial. After some final adjustments, Nathalie, and Andy jumped in the water to adjust the temperatures in the suits. They will be wearing wetsuits, not dry suits because of the problems that are associated with maintain the dry suit environment.

Marcus encouraged Edmond to put on a wet suit to try it out in the lake. For those of you that have put on wet suits before, the task can be quite comical, if not frustrating! We were able to get Edmond out into the lake to test it out, and he seemed to enjoy it. But he equally enjoyed removing the cumbersome equipment!

Marcus soon joined Nathalie and Andy in the lake, and they practiced holding their breath, swimming comfortably in the wetsuits and practiced rescuing an injured diver. All of this went smoothly. It was noted though, that once out of the lake and with the wetsuits of, even with a nice air temp, the wind chill can quickly lower body temperature. It was decided to have a tent available for divers after they are out of the water so they do not have an issue with this problem.

Once out of the water and dry again, each diver tested their blood oxygen level to see if there was a difference in their saturation level. Surprisingly enough, their levels were fairly high after their tests, about 93-95%. But this will not be the case when we are at 19,200 feet. Saturation levels will be much lower, even down to 60-65% because of the low oxygen at that elevation. It seems funny to not only be conducting experiments on the surrounding environment, but on ourselves as well.