If we want to understand the Earth climate and how it is changing, we need to keep track of every day's weather by measuring weather parameters like temperature, wind speed, and atmospheric pressure day by day, at the same time, for decades. Researchers of the Alfred-Wegener-Institut are collecting these weather data with the help of meteorological observatories in the Arctic and Antarctic. Their data is coded after each measurement and transmitted to other research stations as well as to the global data network of the weather services and therefore not only support longterm climate research, but are also help to improve weather forecasts for the polar regions.
Meteorology at Neumayer-Station III, Antarctica
In 2012 the meteorological observatory at the Antarctic Neumayer Station III was officially considered to be a WMO climate observation station by virtue of the fact that meteorologists of the Alfred Wegener Institute have been measuring the air temperature in Antarctica on a daily basis for 30 years. “In 1982 we succeeded for the first time in measuring the air temperature every day of the year. Today, more than 30 years later, our observatory automatically records the air temperature, air pressure, wind speed and other weather data every three hours. They are coded after each measurement and transmitted to other research stations in Antarctica as well as to the global data network of the weather services via e-mail. In this way our measurement data help, for example, to improve weather forecasts,” says meteorologist and scientific head of the observatory Dr. Gert König-Langlo.
To be able to collect reliable temperature data, the meteorologists at the Alfred Wegener Institute used a thermometer of a special kind. It consists of a temperature-sensitive platinum wire protected against solar radiation. It is installed on the observatory tower at a height of two metres, ambient air is swirled around it at every measurement and the data are read out by a computer. “We regularly check the stability of this measuring system by means of reference thermometers,” explains Gert König-Langlo.
Meteorology at AWIPEV research base, Spitsbergen
At the Franco-German research base AWIPEV in Ny-Ålesund, Spitsbergen, scientists have been measuring weather data such as air temperature, air pressure, and humidity regularly since the year 1993. One result of this longterm observation states, that until today the annual mean temperature in Spitzbergen has risen by 1.3 °C. A warming of the Arctic, which becomes apparent especially in winter.
The main climate influence in Ny-Ålesund is the Arctic Ozean. The scientific village is located right at the shoreline of Kongsfjord at the west coast of Spitsbergen, where ocean currents carry warm water from the North Atlantic Ocean. That means, the ocean warms the climate in Spitsbergen, which is why in summer the air gets warmer than 0 °C, while in winter it rarely gets much colder than -25 °C.
In April 2013 the research base was the first meteorological facility in the world to be certified according to the standards of the Global Climate Observing System Reference Upper Air Network (GRUAN) – an international climate reference network initiated by the World Meteorological Organization and partners. "Anyone wishing to understand the climate system of our Earth needs reliable data – for example, on temperature, air pressure and air humidity. However, these measurement data are only reliable and comparable if they are collected in a uniform manner. A bathwater thermometer will, of course, provide a temperature which is distinctly less accurate than a precision thermometer. Meteorological measuring devices can also have different measurement accuracy which is why it is decisive for climate researchers that the measurements taken at the different stations throughout the world are comparable. Only in this way can scientists then derive reliable climate trends from these data”, says AWI meteorologist Dr. Marion Maturilli, head of the meteorological observatory at the Arctic research station.
Meteorological observations on-board RV Polarstern
Without reliable weather data polar expeditions and the related fieldwork become a dangerous undertaking. For this reason there are always two meteorologists working on-board Polarstern. They constantly update the captain and officers, the helicopter crew and the chief scientist about the latest and up-coming weather conditions, so that they can plan ship-based measurements, flights or fieldwork on the ice.
Every day at noon one of the meteorologists releases a weather balloon carrying a device that measures pressure, temperature and humidity, wind direction and wind speed while making its two-hour journey throughout the sky. When reaching approximately 35 km height the balloon explodes, and the atmospheric profile of the day is ended.
The balloon data are transferred in real-time to the ship and used on board for estimating the local weather and the development of the ice conditions around the ship. But most important is that these data are feed into global meteorological models which are essential for forecasting the weather worldwide.