Observations for studies of environmental change in the Antarctic
- This page is part of the topic The Antarctic environment in the global system
As we shall see in more detail in Observations, data accuracy and tools and Antarctic climate and environment change in the instrumental period, lack of observations has long been a problem for scientists working in the Antarctic. The early expeditions were mainly carried out during the brief Antarctic summer, and there is still a bias towards summer observations in some fields – for instance many of the research vessels investigating oceanographic conditions in the Southern Ocean are not equipped to work in the ice-strewn seas of the austral winter, and 24 hour darkness restricts work on land at that time. A major advance was the establishment of research stations that operated year-round. Many stations were constructed around the time of the International Geophysical Year in 1957/58. Most of them still operate today, though not all are year-round. Those with year-round capability monitor many aspects of the Antarctic environment, such as meteorology, solar-terrestrial interactions in the Earth’s outer atmosphere (known as ‘geospace’), coastal sea ice conditions, and sea level. These observations have produced instrumental records that are in many cases 50 years long, providing important data sets for global change studies.
Most research stations are located in the Antarctic coastal region, with only Amundsen-Scott station at the South Pole and Vostok and Concordia on the polar plateau providing in-situ observations from the interior. The advent of satellite remote sensing, beginning with the launch of the meteorological satellite TIROS-1 in April 1960, was therefore crucial for obtaining data from the data-sparse interior of the continent. Initially only visible and infrared imagery were available, but increasingly advanced instruments have been developed that have provided a rich source of data for studies in meteorology, glaciology, geology and observing the surface of the ocean.
To compensate for the difficulties of humans collecting data everywhere on the continent and year-around, there has been a significant rise in the use of automated recording instruments in remote parts of the Antarctic. Automatic weather stations have been deployed at many isolated locations since the early 1980s, to provide data for weather forecasting and climate change studies. Such instruments have sometimes been coupled with equipment to provide upper atmosphere and geospace observations, which is very operationally efficient. Biological studies have also increased, including environmental monitoring at small, biologically relevant scales, although such datasets are typically of short duration. There have been few attempts to link environmental observations across different scales of measurement or between scientific disciplines. Ocean regions have long been a data void for sub-surface oceanographic observations, in particular during winter, but new autonomous systems like Argo floats now complement the subsurface moored systems that provided data over the last two decades in the form of quasi-continuous time series at selected locations. Floating systems are now providing frequent measurements from the subsurface across wide areas, and have the potential to revolutionise our understanding of ocean conditions.
While satellites and autonomous systems can provide valuable data, in some fields the primary forms of data are still collected using in-situ techniques. Ice and sediment cores are the main means of obtaining high-resolution paleoclimate information for the Antarctic. Short cores can be fairly easily collected and provide high horizontal and vertical resolution coverage through the last few hundred years. Deeper ice cores, like those collected at Vostok and Dome C, have provided new insights into the glacial cycles of much of the last million years. Even earlier periods can be investigated with sediment cores from ocean areas, although the resolution there is coarser. Over-snow traverses such as those during IGY and more recently the 21-nation International Trans Antarctic Scientific Expedition (ITASE) serve effectively as polar research vessels. These traverses have now covered many tens of thousands of kilometres. They offer the ground-based opportunities of traditional style traverse travel coupled with the modern technology of GPS navigation, crevasse detecting radar, remote sensing, satellite communications and multi-disciplinary research. By operating as a ground-based transport system, over-snow traverses offer scientists the opportunity to experience the dynamic environment under study.
Naturally, most biological studies involve in-situ measurement and observation, although here again there is some application of satellite or autonomous data, and further potential in this field such as in the monitoring of vegetation extent and the identification of vertebrate colony locations.
In Observations, data accuracy and tools we describe the various kinds of measurements being made, and the advances that they have led to.