26 October, 1996

Subject: Re: Journal 26 October 1996

Live from the Polar Duke enroute to Palmer Station

Location: 64.57S X 63.41W Wind Speed: 10.3 m/sec

Boat Speed: 10.1 knots Wind Direction: 30.7 degrees

Boat Heading: 229 degrees Barometer: 990.98 mb

Humidity: 81.8 % Air Temp.: -1.5 C

Salinity: 32.1 0/00 Water Temp.: -1.2 C

General Weather Conditions: The weather looked promising for our third trip through the Neumeyer Channel. As we approached the Channel so did the large grey clouds. Weather in Antarctica is as changeable as New England weather, if you don't like it wait a minute.

For the third time low scudding clouds obscured our views of what is supposed to be a breathtaking trek to Palmer Station. We had a scheduled stop at Port Lockroy, a British station in the Neumeyer, that was cancelled because of ice, too much and penguins, too few. However, we were able to see the lonely little shack on the edge of the ice that is Port Lockroy.

Because our luck with the Neumeyer had been so dismal the Captain took us over to the Lemaire Channel. This is a cruise ship destination later in the season. It was beautiful, the clouds cleared as we entered the very narrow channel. We saw penguins, whales and seals. The spires of rocks on both sides was breathtaking. I checked out the chart later up on the bridge and saw that we ran between Booth Island and Humphries Heights. The peaks were from 900 to 1200 meters and they had a cathedral-like quality.

>From the Lemaire, we started towards Palmer Station again. About halfway there we stopped for one last CTD cast. This cast was to be our deepest one, 1200 meters, as high as the mountains were in the Lemaire. We decorated syrafoam cups with our lab markers and sent them down with the CTD. The pressure shrinks the cups, they came out great.

Science was now officially over and again we made our way to Palmer Station.

I recieved this in my e-mail the other day and wanted to share it with everyone.

1996 ANTARCTIC OZONE HOLE BELOW RECORD AVERAGE SIZE

Two NASA instruments again have detected substantial depletion of ozone

>levels over Antarctica, commonly referred to as the Antarctic ozone hole. >The average size of the Antarctic ozone hole during 1996 has been almost as >large as in the peak year of 1993, although ozone values are higher than the >record lows seen in September 1994, according to preliminary analysis of >satellite data by scientists at NASA Goddard Space Flight Center in >Greenbelt, MD. During the current year, the ozone hole covered a surface >area over the South Pole roughly equal in size to the North American >continent.

These data were recorded by two of NASA^=D2s Total Ozone Mapping Spectrometer

>instruments (TOMS) launched this year, one on board the NASA Earth Probe >satellite and another on the Japanese Advanced Earth-Observing Satellite >(ADEOS) satellite. Low ozone amounts over the Antarctic continent consistent

>with these TOMS data also have been validated by ground-based instruments and

>other satellite-based instruments.

The average size of the ozone hole during this year was 8.3 million square

>miles, similar to observations in the last four years. The largest observe= >d

>average size of the ozone hole was in 1993, at 8.5 million square miles. >The hole started to form in mid-August of this year and reached a one-day >peak size on Sept. 7, 1996, of about 10 million square miles, then quickly >shrunk to values of less than 8.5 million square miles. The previous largest

>one-day peak size hole was 9.4 million square-miles on Sept. 27, 1992. In >comparison, the surface area of North America is 8.1 million square-miles >while Antarctica has a surface area of 5.4 million square-miles.=20 >Since the mid-1980s, the region covered by low total ozone begins to grow >each year in early August. This region reaches its maximum extent in >September, while the lowest ozone values are typically seen in late September

>and early October. The ozone hole usually disappears by early December. The

>ozone hole in 1996 opened up slightly earlier than in previous years, but had

>begun to decrease in surface area below 7.7 million square-miles by Oct. 16, >1996. "This ozone hole is very similar to those seen in recent years," said Dr.

>Paul Newman, research scientist in the Laboratory for Atmospheres at Goddard.

> "Although its area climbed briefly over that of the previous peak,l that is

>not as great a concern as the average size, because meteorological conditions

>can cause large day-to-day fluctuations. This is similar to winter >temperatures, where one really cold day is not as important as the average >temperature over the whole winter season."

> The ozone amounts measured by TOMS/ADEOS and TOMS/Earth Probe dropped to 111

>Dobson units on Oct. 5 near the center of the Antarctic continent, with >values below 220 Dobson units measured over a wide area. Total ozone values >less than 100 Dobson units were measured in both 1993 and 1994, with the >record low value of 88 Dobson units measured on Sept. 28, 1994. >Ozone, a molecule made up of three atoms of oxygen, comprises a thin layer of

>the atmosphere which absorbs harmful ultraviolet radiation from the Sun. A

>Dobson unit is related to the physical thickness of the ozone layer if it >were brought to the Earth^=D2s surface. The global average ozone layer >thickness is 300 Dobson units, which equals 1/8th of an inch, approximately >the thickness of two stacked pennies. In contrast, the ozone layer thickness

>in the ozone hole is about 100 Dobson units (1/25th of an inch), >approximately the thickness of a single dime.

Scientists at the South Pole from the National Oceanic and Atmospheric >Administration (NOAA), working with balloon-borne measurements, have found >low total ozone values similar to those seen in 1995. "However, in the >central region of the ozone hole, from 7.5 to 12.5 miles altitude, ozone >depletion was more severe than in the past," said Dr. Dave Hofmann of the >NOAA Climate Monitoring and Diagnostics Lab in Boulder, CO. The NOAA >measurements showed that complete destruction of ozone at an altitude of 10 >miles was observed over the period from Sept. 24 to Oct. 14. "Total ozone >did not reach record lows because of unusually high ozone above the ozone >hole at 15 miles which compensated for the low values in the ozone hole," >Hofmann said.

> "These deep and large ozone holes are likely to continue to form annually

>until the stratospheric chlorine amount drops to its pre-ozone hole values," >said Dr. Richard Stolarski, also a research scientist at Goddard. "The >slightly earlier ozone hole this year probably resulted from the continued >increase of Antarctic stratospheric total chlorine levels." >Since the discovery of the ozone hole in 1985, TOMS has been a key instrument

>for monitoring ozone levels throughout the southern hemisphere. The firstl

>for monitoring ozone levels throughout the southern hemisphere. The first >TOMS aboard NASA Nimbus-7 satellite measured Antarctic ozone levels from >November 1978 to May 1993, and it helped make ozone a household word through >pictures of the Antarctic ozone hole. It was followed by a TOMS sensor on a

>Russian satellite.

> TOMS data also provided part of the scientific underpinning for the Montreal

>Protocol, under which many of the world^=D2s nations have agreed to phase out

>the use of ozone-depleting chemicals. As a result of restrictions in the >Montreal Protocol, chlorine levels have already peaked in the lower >atmosphere, and should peak in the Antarctic stratosphere in about three to five years.

>The size and depth of the ozone hole, and global ozone levels, depend on >meteorological conditions and on the amount of chlorine present in the >atmosphere, and may be affected by the presence of sulfate aerosols produced >by volcanic eruptions. Scientists speculate that ozone values over >Antarctica were low in 1993 and 1994 because of the enhanced presence of >sulfuric acid aerosols in the stratosphere due to the June 1991 Mount >Pinatubo eruption in the Philippines.

TOMS-Earth Probe, launched in July of this year, is the third in the series

>of TOMS instruments. Operating from a 312-mile orbit, TOMS-Earth Probe is >principally dedicated to collecting ozone and aerosol data in the lower >atmosphere. The fourth TOMS instrument was launched in August aboard ADEOS >into a 500-mile orbit. ADEOS is an international climate change research >mission that includes instruments from the U.S., Japan, and France, with >investigators from many countries around the world.

> Both TOMS-EP and ADEOS are key parts of a global environmental effort which

>includes NASA Mission to Planet Earth, a long term, coordinated research >effort to study the Earth as a global environmental system.

> TOMS ozone data and pictures are available to anyone with a computer >connection to the Internet World Wide Web at: >http://jwocky.gsfc.nasa.gov

>The TOMS instruments are managed by the Goddard Space Flight Center for >NASA^=D2s Office of Mission to Planet Earth, Washington, DC.=20 >=B7 end-

Steven Stevenoski

Lincoln High School

Wisconsin Rapids, WI 54494

Antarctic Link Project/Project Glacier