You've asked ?s, We've got answers.

Students at Indian River State College (Florida) in Ms. Weiss's "Introduction to Oceanography" course were kind enough to send us some questions.  The field team is trying to answer as many of these as they can in their downtime, but now that the weather has gotten much better, we've still got a lot of stations to do. Here are a couple of answers and we're working on the rest.

These questions were answered by Karen.

1) While being in Antarctica can you see the effects of global warming occurring? Do you think it will get better or worse in the years to come?

This is my first trip to Antarctica, so I have nothing with which to compare what I see here now. However, I asked our Marine Projects Coordinator, Herb, who told me that he has been visiting and living on Antarctica for “longer than you [I] have been alive.” This means that Herb has seen the Antarctic continent regularly for at least the past 27 years. There is a glacial behind Palmer Station that you can hike up. Herb has noticed that in recent years you have to walk a lot longer on rock to start your hike up the glacier. In many parts of Antarctica, glaciers and ice are receding. It is safe to say that temperatures here are getting warmer, causing all this ice to melt more than in the recent past. [Joe: Studies have shown that the Antarctic peninsula region (where we are) is warming at a much more rapid rate than the global average.  But, making things even more complicated, some studies have shown that the interior of Antarctica is actually getting cooler.  This can often lead to confusion if somebody says "Antarctica is warming" as most studies that have found trends or significant changes are looking at a sub-area and not the entire continent.]

Regarding whether this will “get better or worse” in years to come, it is important to realize that environmental change like warming temperatures in the Antarctic is not a question of better or worse. Environmental change can be beneficial to some organisms, while detrimental to others. Some creatures and ecosystems show more resilience than others, being affected more or less depending on the level and rate of change. It does seem that this warming trend is continuing, but the mechanisms behind such change are complex and related to processes all over the globe. Therefore, it is difficult to say with certainty whether it will continue at all, continue at the same rate, or continue at a steeper rate.

4) What was the most amazing discovery that you have come across while conducting your research?

While I have not discovered anything new to mankind, I have discovered things that were new to me. While working on zooplankton and right whales off of Cape Cod, Massachusetts, I have come to appreciate the magnitude to which right whale food (copepods) controls the behavior and distribution of these animals. It appears that using information just about zooplankton and certain other environmental variables, one can actually predict the presence or absence of right whales, as well as their behavior, with statistically significant positive results. To me, the strength of this relationship between right whales and their feeding habitat is quite amazing. [Joe: My last research trip here in May and June of this year was examining the very same process Karen was describing except instead of copepods and right whales, we were looking at krill and humpback whales.]

8) What is there to gain from studying life forms such as zooplankton in this region? Could depletion of animals in the Antarctic impact communities in other bodies of water?

There are many things we can learn about the Antarctic marine ecosystem, and other ecosystems around the world, by studying zooplankton here. Secondary production [the growth of animals that eat primary producers or plants] not only provides an integral part of the marine food web foundation, but is also important to nutrient cycling and carbon flux. Salps, for example, produce fecal matter that contains carbon, and sinks to the seafloor after being excreted. This is a type of carbon sink, which removes CO₂ from the air (in the form of photosynthesis in phytoplankton) and moves it to the seafloor. Studying changes in zooplankton production here, and the mechanisms behind that change, can give us insights into how widespread certain phenomena are in the world’s oceans. Comparative studies are becoming increasingly important as we discover more ways in which Earth’s ocean waters and atmosphere are connected.

Depletion of animals in the Antarctic can impact communities in other bodies of water on in a number of ways. As mentioned above, the importance of zooplankton production to remove carbon from the upper ocean directly relates to the amount of carbon in the atmosphere; the whole world is affected by the amount of carbon in the atmosphere. Also, many large whales travel from other parts of the world to the Antarctic to feed in the summertime. Humpback whales that winter in the South Pacific, for example, feed on krill here. A decrease in krill here would lead to a decrease in food availability for certain humpback populations, and therefore their overall success (calving, longevity, health, etc).

- Karen ([and Joe])