Albedo is the fraction of sunlight that is diffusely reflected by a body. It is measured on a scale from 0 to 1. Surface albedo is defined as the ratio of radiosity Je to the irradiance Ee received by a surface. The proportion reflected is not only determined by properties of the surface itself, but also by the spectral and angular distribution of solar radiation reaching the Earth's surface. These factors vary with atmospheric composition, geographic location, and time.
The greenhouse effect occurs when greenhouse gases in a planet's atmosphere insulate the planet from losing heat to space, raising its surface temperature. Surface heating can happen from an internal heat source as in the case of Jupiter, or from its host star as in the case of the Earth. In the case of Earth, the Sun emits shortwave radiation (sunlight) that passes through greenhouse gases to heat the Earth's surface. In response, the Earth's surface emits longwave radiation that is mostly absorbed by greenhouse gases. The absorption of longwave radiation prevents it from reaching space, reducing the rate at which the Earth can cool off.
The cryosphere is an all-encompassing term for the portions of Earth's surface where water is in solid form, including sea ice, lake ice, river ice, snow cover, glaciers, ice caps, ice sheets, and frozen ground. Thus, there is a wide overlap with the hydrosphere. The cryosphere is an integral part of the global climate system. It also has important feedbacks on the climate system. These feedbacks come from the cryosphere's influence on surface energy and moisture fluxes, clouds, the water cycle, atmospheric and oceanic circulation.
Sea ice arises as seawater freezes. Because ice is less dense than water, it floats on the ocean's surface. Sea ice covers about 7% of the Earth's surface and about 12% of the world's oceans. Much of the world's sea ice is enclosed within the polar ice packs in the Earth's polar regions: the Arctic ice pack of the Arctic Ocean and the Antarctic ice pack of the Southern Ocean. Polar packs undergo a significant yearly cycling in surface extent, a natural process upon which depends the Arctic ecology, including the ocean's ecosystems. Due to the action of winds, currents and temperature fluctuations, sea ice is very dynamic, leading to a wide variety of ice types and features. Sea ice may be contrasted with icebergs, which are chunks of ice shelves or glaciers that calve into the ocean. Depending on location, sea ice expanses may also incorporate icebergs.
The Geostationary Earth Radiation Budget (GERB) is an instrument aboard EUMETSAT's Meteosat Second Generation geostationary satellites designed to make accurate measurements of the Earth radiation budget.
Earth's energy budget accounts for the balance between the energy that Earth receives from the Sun and the energy the Earth loses back into outer space. Smaller energy sources, such as Earth's internal heat, are taken into consideration, but make a tiny contribution compared to solar energy. The energy budget also accounts for how energy moves through the climate system. The Sun heats the equatorial tropics more than the polar regions. Therefore, the amount of solar irradiance received by a certain region is unevenly distributed. As the energy seeks equilibrium across the planet, it drives interactions in Earth's climate system, i.e., Earth's water, ice, atmosphere, rocky crust, and all living things. The result is Earth's climate.
This is a list of meteorology topics. The terms relate to meteorology, the interdisciplinary scientific study of the atmosphere that focuses on weather processes and forecasting.
Ice algae are any of the various types of algal communities found in annual and multi-year sea, and terrestrial lake ice or glacier ice.
A pressure ridge, when consisting of ice in an oceanic or coastal environment, is a linear pile-up of sea ice fragments formed in pack ice by accumulation in the convergence between floes.
Polar meteorology is the study of the atmosphere of Earth's polar regions. Surface temperature inversion is typical of polar environments and leads to the katabatic wind phenomenon. The vertical temperature structure of polar environments tends to be more complex than in mid-latitude or tropical climates.
The climate of the Arctic is characterized by long, cold winters and short, cool summers. There is a large amount of variability in climate across the Arctic, but all regions experience extremes of solar radiation in both summer and winter. Some parts of the Arctic are covered by ice year-round, and nearly all parts of the Arctic experience long periods with some form of ice on the surface.
The Global Energy and Water Exchanges Project is an international research project and a core project of the World Climate Research Programme (WCRP).
Arctic geoengineering is a type of climate engineering in which polar climate systems are intentionally manipulated to reduce the undesired impacts of climate change. As a proposed solution to climate change, arctic geoengineering is relatively new and has not been implemented on a large scale. It is based on the principle that Arctic albedo plays a significant role in regulating the Earth's temperature and that there are large-scale engineering solutions that can help maintain Earth's hemispheric albedo. According to researchers, projections of sea ice loss, when adjusted to account for recent rapid Arctic shrinkage, indicate that the Arctic will likely be free of summer sea ice sometime between 2059 and 2078. Advocates for Arctic geoengineering believe that climate engineering methods can be used to prevent this from happening.
Measurement of sea ice is important for safety of navigation and for monitoring the environment, particularly the climate. Sea ice extent interacts with large climate patterns such as the North Atlantic oscillation and Atlantic Multidecadal Oscillation, to name just two, and influences climate in the rest of the globe.
Sea ice concentration is a useful variable for climate scientists and nautical navigators. It is defined as the area of sea ice relative to the total at a given point in the ocean. This article will deal primarily with its determination from remote sensing measurements.
Sea ice is a complex composite composed primarily of pure ice in various states of crystallization, but including air bubbles and pockets of brine. Understanding its growth processes is important for climate modellers and remote sensing specialists, since the composition and microstructural properties of the ice affect how it reflects or absorbs sunlight.
The Arctic ice pack is the sea ice cover of the Arctic Ocean and its vicinity. The Arctic ice pack undergoes a regular seasonal cycle in which ice melts in spring and summer, reaches a minimum around mid-September, then increases during fall and winter. Summer ice cover in the Arctic is about 50% of winter cover. Some of the ice survives from one year to the next. Currently, 28% of Arctic basin sea ice is multi-year ice, thicker than seasonal ice: up to 3–4 m (9.8–13.1 ft) thick over large areas, with ridges up to 20 m (65.6 ft) thick. Besides the regular seasonal cycle there has been an underlying trend of declining sea ice in the Arctic in recent decades as well.
The Multidisciplinary drifting Observatory for the Study of Arctic Climate expedition was a one-year-long expedition into the Central Arctic. For the first time a modern research icebreaker was able to operate in the direct vicinity of the North Pole year round, including the nearly half year long polar night during winter. In terms of the logistical challenges involved, the total number of participants, the number of participating countries, and the available budget, MOSAiC represents the largest Arctic expedition in history.
False bottom is a form of sea ice that forms at the interface between meltwater and seawater via the process of double-diffusive convection of heat and salt.
An ice mass balance buoy (IMB) allows scientists studying sea ice to measure its temperature and the evolution of its interfaces remotely. The autonomous mass balance buoys usually consist of a data controller module and a temperature string. Some ice mass balance buoys also include acoustic sounders above and below ice measuring the positions of the snow-ice and ice-water interfaces.
