Electric heatingElectric heating is a process in which electrical energy is converted directly to heat energy. Common applications include space heating, cooking, water heating and industrial processes. An electric heater is an electrical device that converts an electric current into heat. The heating element inside every electric heater is an electrical resistor, and works on the principle of Joule heating: an electric current passing through a resistor will convert that electrical energy into heat energy.
Heating, ventilation, and air conditioningHeating, ventilation, and air conditioning (HVAC) is the use of various technologies to control the temperature, humidity, and purity of the air in an enclosed space. Its goal is to provide thermal comfort and acceptable indoor air quality. HVAC system design is a subdiscipline of mechanical engineering, based on the principles of thermodynamics, fluid mechanics, and heat transfer. "Refrigeration" is sometimes added to the field's abbreviation as HVAC&R or HVACR, or "ventilation" is dropped, as in HACR (as in the designation of HACR-rated circuit breakers).
Water on MarsAlmost all water on Mars today exists as ice, though it also exists in small quantities as vapor in the atmosphere. What was thought to be low-volume liquid brines in shallow Martian soil, also called recurrent slope lineae, may be grains of flowing sand and dust slipping downhill to make dark streaks. While most water ice is buried, it is exposed at the surface across several locations on Mars. In the mid-latitudes, it is exposed by impact craters, steep scarps and gullies.
Boundary layerIn physics and fluid mechanics, a boundary layer is the thin layer of fluid in the immediate vicinity of a bounding surface formed by the fluid flowing along the surface. The fluid's interaction with the wall induces a no-slip boundary condition (zero velocity at the wall). The flow velocity then monotonically increases above the surface until it returns to the bulk flow velocity. The thin layer consisting of fluid whose velocity has not yet returned to the bulk flow velocity is called the velocity boundary layer.
Ocean heat contentOcean heat content (OHC) is the energy absorbed and stored by oceans. To calculate the ocean heat content, measurements of ocean temperature at many different locations and depths are required. Integrating the areal density of ocean heat over an ocean basin, or entire ocean, gives the total ocean heat content. Between 1971 and 2018, the rise in OHC accounted for over 90% of Earth’s excess thermal energy from global heating. The main driver of this OHC increase was anthropogenic forcing via rising greenhouse gas emissions.
DownwellingDownwelling is the process of accumulation and sinking of higher density material beneath lower density material, such as cold or saline water beneath warmer or fresher water or cold air beneath warm air. It is the sinking limb of a convection cell. Upwelling is the opposite process, and together, these two forces are responsible in the oceans for the thermohaline circulation. The sinking of the cold lithosphere at subduction zones is another example of downwelling in plate tectonics.
Sea surface temperatureSea surface temperature (SST), or ocean surface temperature, is the ocean temperature close to the surface. The exact meaning of surface varies according to the measurement method used, but it is between and below the sea surface. Air masses in the Earth's atmosphere are highly modified by sea surface temperatures within a short distance of the shore. Localized areas of heavy snow can form in bands downwind of warm water bodies within an otherwise cold air mass.
Ocean stratificationOcean stratification is the natural separation of an ocean's water into horizontal layers by density, which is generally stable because warm water floats on top of cold water, and heating is mostly from the sun, which reinforces that arrangement. Stratification is reduced by wind-forced mechanical mixing, but reinforced by convection (warm water rising, cold water sinking). Stratification occurs in all ocean basins and also in other water bodies.
Joule heatingJoule heating, also known as resistive, resistance, or Ohmic heating, is the process by which the passage of an electric current through a conductor produces heat. Joule's first law (also just Joule's law), also known in countries of former USSR as the Joule–Lenz law, states that the power of heating generated by an electrical conductor equals the product of its resistance and the square of the current: Joule heating affects the whole electric conductor, unlike the Peltier effect which transfers heat from one electrical junction to another.
Turbidity currentA turbidity current is most typically an underwater current of usually rapidly moving, sediment-laden water moving down a slope; although current research (2018) indicates that water-saturated sediment may be the primary actor in the process. Turbidity currents can also occur in other fluids besides water. Researchers from the Monterey Bay Aquarium Research Institute found that a layer of water-saturated sediment moved rapidly over the seafloor and mobilized the upper few meters of the preexisting seafloor.
