Although my advisor, Dr. Chu, is quite happy with the data collected in March, it is my obligation to get enough data. I am determined to collect lidar data as much as possible. At the beginning of April, I thought the weather would be better and better, but the fact is that it was worse than March.

"X file", Milk Way X Aurora

As the nights are getting longer and longer, there are more and more challenges. The first challenge is that it is very hard to judge whether the sky is clear enough to take data.  The night of 6 April 2011, I rushed to Arrival Heights to prepare for taking data. When I just got off my truck, I saw a huge “X” above my head. One was Milk way, but what was the other, light green “clouds” moving back and forth? The whole sky was brilliantly ­­­­­­­­­lighted up. My mind went blank for several minutes. It was so beautiful and so quiet. When I realized it was an aurora, it was already a few minutes later. I hurried to set up my camera and took the shot. It was the first time I saw aurora at McMurdo, at Antarctic. It was cool!

Morning Aurora

Aurora, shooting star, and lidar beams

Aurora, NASA Dome

Exciting data were collected on 7-8 April 2011 when aurora activities were very strong over Arrival Heights again. I didn’t have a chance to take data the previous night. Now the system had been taking data for almost 24 hours. The aurora started at midnight of 7 April, and lit the sky until early morning 8 April. Accompanied with the aurora event, the data collected 7-8 April showed a lot of interesting and exciting phenomena.  Further study is already going on.

The ice was frozen by the end of March, but somehow it opened again in mid-April. The bad weather conditions prevented me from collecting data for about 10 days. In one week, there were two storms and more than 3 days were Condition Two. The open water increased humidity, and pushed the temperature up to -5 Celsius degree once in awhile — incredibly warm. However, strong turbulence generated strong wind gusts. The strongest wind was over 100 knots.  Toward the end of April, the air began to calm.

Lonely Arrival Heights

During this time, I worked with Sean to resolve the cold-air-ducting problem, which has intolerable negative influences on the performance of two turning mirrors. Once I opened the caps of the beam tubes, the cold air could be ducted to the turning mirrors and could cool the mirrors and mirror mounts down to -1 Celsius degree. The huge temperature change led to a dramatic drifting of the positions of turning mirrors.  Dr. Chu and I designed a simple setup, using two heat guns blowing upward air through the beam tubes. I told our ideas to Sean. Sean is the supervisor of Science Support Center and has done numerous winters over at McMurdo.  He helped me to implement the ideas and did a great job on installing the “anti-cold air” device.

Open water surrounding the Ross Island generated so many clouds. We ran into a few times of conditions II. In March, there was not even a single day with continuous 24 hours of clear skies. My tries to run the lidar were frustrated by the cloudy sky and quick weather change. But eventually I managed to collect more than 50 hours of lidar data in March.

Goodbye summer

Toast to winter by station manager

As the summer people left, the population at Mc town went down significantly. It shrunk from 1000 to 151. The last flight took off on March 5, 2011. On that day, we had a traditional champagne toast to celebrate the moment. Since it was a work day, most people were on duty. Only around 30 people attended the toast. Bill Henriksen, the NSF Station Manager, gave a short speech. Winter season began formally. For the senior winter folks as well as the fresh winter people, it was a memorial moment.  For me, it’s a long way down. When the airbus flew over our heads, I lift a glass of champagne, murmured, “Toast, Winter, Lidar!”

Toast to lidar project

Last flight out of McM

On March 18, 2011, I ran into the first problem that scared me. It was at midnight, and I saw the stars were beginning to show up in the north sky. I knew it could be the only chance of clear sky for the next few days, so I rushed to Arrival Heights. Before turning on everything, I decided to run the system with nighttime configuration, and it would be the first time I tried to switch the daytime configuration to nighttime configuration by myself, while the whole system was running. Unfortunately, I encountered a series of problems. A pulse-prohibition box couldn’t be powered on. I fixed the problem quickly after some diagnosis. However, it turned out this was just the start of troubles.

When everything was ready and the system began to take data, some weird phenomena drew my attention.  First, I noticed that the computer couldn’t communicate with SR430 on the 372-nm channel. Soon, I found the PMT current of the 372-nm channel was unstable. These two points really scared me as they could mean very severe problems. Restarting the PMT, computer and SR 430 didn’t help. Finally, I had to turn off the 372-nm channel, and run the 374-nm channel for data.  Every step I had done was within the standard procedure, and I realized the problems might have reached beyond my capability.

Several hours later, I got in touch with Dr. Chu and other members in our group. Dr. Chu helped me to analyze the issues comprehensively, and she instructed me on how to diagnose and solve these problems carefully. Finally, we solved the problem nicely, and everything went back to normal. I feel so grateful to my group for their help and encouragement, especially Dr. Chu.

Milky Way

"Pearl" in the dark

Finally we can see the nighttime sky after several months of 24-hour daylight. The night sky at McMurdo is so beautiful, and the station in the night looks so different from its summer appearance.

By mid-February 2011, I was “left” alone and became the sole operator for our Fe Boltzmann lidar through the first winter season at McMurdo.

What a wonderful and big family we had in the summer at McMurdo! I really enjoyed working with my professors and colleagues. By January 22, 2011, my advisor, Prof. Xinzhao Chu, flew out of Antarctica and returned to the University of Colorado. Prof. Chet Gardner left at the end of January and flew back to the University of Illinois. Two of the summer crew, Dr. Wentao Huang and Mr. Weichun Fong, were finally redeployed by February 14, 2011.

On Feb. 15, the second day after the summer crew left, the sky became clear and I went to Arrival Heights to turn on the lidar system. About 12 hours of data were collected, and I was happy and confident in running the lidar by myself.

Now I have the “freedom” to run the lidar whenever the sky is clear and no longer need to worry about the electromagnetic interference (EMI) issues. I am really grateful to many people who helped resolve the EMI issues, especially my advisor and USAP engineers. Under their push for the installation of 3-phase line filters in mid-January and the installation of a “separation” transformer in early February, the Arrival Heights EMI between LIDAR and VLF experiments has been eliminated completely. Our tests in February show that the LIDAR doesn’t have any effect on the VLF noise background anymore. Both US and Kiwi VLF noise spectrum background is completely independent of LIDAR operation. Furthermore, the VLF noise background becomes even better than that prior to the LIDAR installation.

Golden vessel, Palmer

"I believe I can fly", Adelie penguin

The landscape began to change in late February. The golden color painted by the sunset and sunrise makes McMurdo a different town than in the summer. Here are a few shots. The first one is the Palmer gleaming gold in the shine of the setting sun. It was the last time that the Palmer had been anchored inside McMurdo harbor for the 2010~2011 season. I was also lucky to obtain a “VIP” tour, when I met a graduate student studying marine biology who was on a Palmer cruise with his advisor. The Palmer, named after a U.S. seal hunter Nathaniel Palmer who was believed the first to discover the continent, has icebreaking capability to support around 90 crew members for a 2-month cruise. At the end of my tour, I was happy to be a “Captain” for a while in the control room.

Boarding Palmer

"Captain Yu"

As a gateway to access McMurdo, Christchurch, New Zealand, is familiar to every USAP participant. An earthquake, magnitude 6.3, struck the city again in February.  The Feb 22^nd earthquake was closer in distance and shallower in depth to the city of Christchurch than its September 2010 quake. At that time, there were 388 USAP people in Christchurch, and at McMurdo there were several hundred more waiting for the flight coming from Christchurch. What’s worse, we encountered the first severe storm since I came down to McMurdo. The storms in Pegasus field, our airport, reached Condition One. In Mc town, it was Condition Two. The storm buried the ice runway, and made the road from Scott Base out onto the ice shelf en route to Pegasus disintegrate rapidly. It seemed the bad things came altogether. However, we have an incredible group of people in this program, who truly shine in these difficult times. Moving fuel lines, building a new road, and cleaning were quickly done by McMurdo personnel. Finally, all the summer people flew out of the ice by March 5, 2011.