ARCTIC

The Arctic consists of ocean surrounded by continental land masses and islands. The central Arctic Ocean is ice-covered year-round, and snow and ice are present on land for most of the year.
The southern limit of the arctic region is commonly placed at the Arctic Circle (latitude 66 degrees, 32 minutes North). The Arctic Circle is an imaginary line that marks the latitude above which the sun does not set on the day of the summer solstice (usually 21 June) and does not rise on the the day of the winter solstice (usually 21 December). North of this latitude, periods of continuous daylight or night last up to six months at the North Pole.
Arctic researchers also define the Arctic region as:
The area north of the treeline (the northern limit of upright tree growth)
Locations in high latitudes where the average daily summer temperature does not rise above 10 degrees Celsius

Weather is the day-to-day state of the atmosphere, and its short-term (minutes to weeks) variation. Popularly, weather is thought of as the combination of temperature, humidity, precipitation, cloudiness, visibility, and wind. We talk about the weather in terms of "What will it be like today?", "How hot is it right now?", and "When will that storm hit our section of the country?"
Climate is defined as statistical weather information that describes the variation of weather at a given place for a specified interval. In popular usage, it represents the synthesis of weather; more formally it is the weather of a locality averaged over some period (usually 30 years) plus statistics of weather extremes.
We talk about climate change in terms of years, decades or even centuries. Scientists study climate to look for trends or cycles of variability (such as the changes in wind patterns, ocean surface temperatures and precipitation over the equatorial Pacific that result in El Niño and La Niña), and also to place cycles or other phenomena into the bigger picture of possible longer term or more permanent climate changes.


Synoptic meteorology is the study and analysis of weather information obtained simultaneously over a wide area. Observations are collected simultaneously in order to obtain a comprehensive and nearly instantaneous picture of the state of the atmosphere.
Synoptic weather observations are made periodically (usually at three-hourly and six-hourly intervals as specified by the World Meteorological Organization). Information collected about weather is shared worldwide via the Global Telecommunications System (GTS).
A synoptic chart is a map presenting data and analyses that describe the state of the atmosphere over a large area at a given moment in time. Synoptic-scale weather is characterized by migrating storms, air masses, and fronts, such as those highlighted on television and newspaper weather maps.
The objective of synoptic meteorology is to forecast weather. Forecasting the weather is a complicated and expensive process, with forecasters requiring extensive training to be able to make accurate predictions. Weather forecasters use data about wind patterns, temperature, moisture, and pressure prevailing across the globe to predict developing weather patterns. Computer-based numerical models are used to create short-term (24 hour to 48 hour) forecasts and extended range predictions for three days or more.

The arctic climate is characterized by high spatial variability, and includes both polar maritime (influenced by the ocean) and continental (influenced by large land masses) climate subtypes. The main constant is that the climate in all arctic areas is affected by the extreme solar radiation conditions of high latitudes.
For example, the amount of solar radiation received in summer along the Siberian arctic coast compares favorably, by virtue of the long period of daylight, with that in lower middle latitudes. However, the low sun angle (elevation of the sun above the horizon) means that even minor topographic features, such as low hills, can cause major differences in climate at the local level by shading. Even though the Arctic receives a large amount of solar energy in summer, the high reflectivity (albedo) of snow and ice surfaces keeps absorption of solar energy low. Therefore, the heat gained during the long summer days is small and highly dependent on surface properties such as topography and albedo. For instance, wet tundra and bare ground (with low albedo) absorb more solar radiation than do high-albedo ice sheets. Similarly, wet snow absorbs more radiation than dry snow. Solar radiation is small or absent in winter.
Maritime climate conditions prevail over the Arctic Ocean, coastal Alaska, Iceland, northern Norway and adjoining parts of Russia. In these areas, winters are cold and stormy. Summers are cloudy but mild with mean temperatures about 10 degrees Celsius. Annual precipitation is generally between 60 cm and 125 cm, with a cool season maximum (largely snowfall) and about six months of snow cover.
The interior, continental climates have much more severe winters, although precipitation amounts are less. In these regions, permafrost (permanently frozen ground) is wide-spread and often of great depth. In summer, only the top one to two meters of ground thaw. Since the water cannot readily drain away, this "active layer" often remains waterlogged. Although frost may occur in any month, long summer days usually provide three months with mean temperatures above 10 degrees Celsius, and at some stations in the continental interiors temperatures can exceed 30 degrees Celsius.
In winter, arctic weather is dominated by the frequent occurrence of inversions (when warm air lies above a colder air layer near the surface). The inversion layer decouples the surface wind from the stronger upper layer wind. For this reason, surface wind speeds tend to be lower in winter than one might expect. In summer, inversions are less frequent and weaker, and arctic weather patterns are dominated by the movement of low pressure systems (cyclones) across Siberia and into the Arctic Basin.
In many arctic and subarctic regions, the weather is controlled by semipermanent low pressure systems that are weakly developed in summer, but stronger in winter. The most important of these low pressure systems are the Icelandic Low and the Aleutian Low. In winter, eastern Eurasia is dominated by the semipermanent Siberian High. High pressure is also prevalent over the Canadian Arctic Archipelago during the cold season.

Animal and plant life
Endangered marine species include walruses and whales. The area has a fragile ecosystem which is slow to change and slow to recover from disruptions or damage.
The Arctic Ocean has relatively little plant life except for phytoplankton. Phytoplankton are a crucial part of the ocean and there are massive amounts of them in the Arctic. Nutrients from rivers and the currents of the Atlantic and Pacific oceans provide food for the Arctic phytoplankton. During summer, the Sun is out day and night, thus enabling the phytoplankton to photosynthesize for long periods of time and reproduce quickly. However, the reverse is true in winter where they struggle to get enough light to survive.