Characteristics
- Extreme oscillations in irradiance: in polar regions, for months it may be totally dark (in winter) or light (in summer). Because of the existence of polar ice, surface reflectance of sunlight is very high. In addition the solar angle are relatively quite low. So less light can penetrate into water and becomes bio available to the plants in polar water under the ice cover.
- Water temperatures are low, but do not change much seasonally. The low temperature and low available high irradiance together limit primary production.
- Major nutrients (N, P, Si) are often not limiting primary production.
- Blooming of Phytoplankton happens in summer, because of the decreased salinity (sea ice melt-water), lower mixing, higher stratification, higher temperature and more bio available light.
- Ice is very important in structuring environment. It regulates the physics, chemistry and biology of the water column, air-sea exchange, and is also an important habitat.
Read more about this topic: Polar Seas