2. Atmosphere Key Terms Flashcards
9696 - Cambridge AS Geography
Diurnal Energy Budget
The balance between the incoming and outgoing energy of the Earth’s surface over a 24-hour period.
Incoming (Shortwave) Solar Radiation
The energy emitted by the sun that reaches the Earth’s surface in the form of visible and ultraviolet light.
Reflected Solar Radiation
The portion of incoming solar radiation that bounces back into the atmosphere without being absorbed by the Earth’s surface.
Energy Absorbed into the Surface and Subsurface
The portion of incoming solar radiation that is absorbed by the Earth’s surface and heats it up, some can also penetrate and heat the subsurface.
Albedo
The proportion of incoming solar radiation that is reflected back into the atmosphere by a surface.
Sensible Heat Transfer
The transfer of heat between the Earth’s surface and the atmosphere through direct contact. Warm surfaces transfer heat to the cooler air, and vice versa.
Longwave Radiation
The infrared radiation emitted by the Earth’s surface and atmosphere back towards space.
Latent Heat Transfer
The transfer of heat that occurs when water changes state (evaporation) or returns to a liquid state (condensation). Evaporation requires energy from the surroundings, cooling the surface, while condensation releases energy, warming the surroundings.
Evaporation
The process by which liquid water changes into a gas and enters the atmosphere. This process absorbs energy from the surrounding environment, leading to a cooling effect.
Dew
Water vapor that condenses on objects at night when the surface temperature falls below the dew point. This process releases energy, slightly warming the surface.
Longwave Radiation from the Atmosphere
Some of the longwave radiation emitted by the Earth’s surface is trapped by greenhouse gases in the atmosphere and re-radiated back towards the surface, contributing to warming.
Global Energy Budget
The balance between incoming solar radiation and outgoing Earth radiation that determines the planet’s average temperature.
Latitudinal Pattern of Radiation
The variation in the amount of solar radiation received by the Earth’s surface at different latitudes.
Excesses
Areas that receive more solar radiation than they emit back into space, typically occurring at lower latitudes.
Deficits
Areas that emit more radiation than they receive from the sun, typically occurring at higher latitudes.
Atmospheric Transfers
Processes by which heat is redistributed around the globe through the movement of air and water.
Wind Belts
Large-scale, persistent atmospheric circulation patterns characterized by prevailing wind directions.
Ocean Currents
Large-scale, continuous flows of water in the oceans driven by wind, temperature, and salinity differences.
Seasonal Variations
Changes in temperature, pressure, and wind belts throughout the year.
Influence of Latitude
The angle of the sun’s rays varies with latitude, affecting the amount of solar radiation received and influencing temperature patterns.
Land-Sea Distribution
Land heats and cools faster than water. This uneven heating creates pressure differences that drive atmospheric circulation and influence wind patterns.
Ocean Currents
Warm ocean currents transport heat towards higher latitudes, moderating their climates. Cold currents transport heat away from polar regions.
Atmospheric Moisture Processes
Processes that govern the movement and transformation of water vapor in the atmosphere.
Evaporation
The process where liquid water changes into a gas and enters the atmosphere.
Condensation
The process by which water vapor changes into a liquid state, forming clouds or dew.
Freezing
The process where water vapor or liquid water changes into ice crystals.
Melting
The process where ice or snow changes into liquid water.
Deposition
The process by which water vapor changes directly into ice crystals, bypassing the liquid stage. This is common in the formation of frost and some types of snow.
Sublimation
The process where solid ice or snow changes directly into water vapor without melting into liquid water first.
Causes of Precipitation
Mechanisms that lift and cool air, leading to condensation and precipitation.
Convection
Warm air rises, cools, and condenses as it reaches higher altitudes, forming clouds and rain.
Frontal Uplift
When warm and cold air masses meet, the warm air is forced to rise over the cooler air, leading to condensation and precipitation along the frontal boundary.
Orographic Uplift
As air is forced to rise over mountains, it cools and condenses, producing precipitation on the windward side of the mountains.
Radiation Cooling
At night, the Earth’s surface loses heat through radiation, cooling the air in contact with it. This cooling can lead to condensation and fog formation.
Types of Precipitation
Different forms of water that fall to the Earth’s surface from the atmosphere.
Clouds
Visible collections of water droplets or ice crystals suspended in the atmosphere.
Rain
Liquid water droplets that fall to the Earth’s surface from clouds.
Hail
Balls or lumps of ice that form within cumulonimbus clouds and fall to the ground.
Snow
Frozen water vapor that condenses directly into ice crystals in the atmosphere and falls to the ground as flakes.
Dew
Water vapor that condenses on objects at night when the surface temperature falls below the dew point.
Fog
A visible collection of water droplets or ice crystals suspended near the Earth’s surface, reducing visibility.
Human Impact
The ways in which human activities are affecting the Earth’s climate.
Greenhouse Effect
The natural process by which certain gases in the atmosphere trap heat from the sun, warming the planet.
Enhanced Greenhouse Effect
Human activities are increasing the concentration of greenhouse gases in the atmosphere, amplifying the natural greenhouse effect and causing global warming.
Global Warming
The long-term increase in the average global temperature of the Earth’s atmosphere and oceans.
Rising Global Temperatures
Direct temperature measurements show an increase in average global temperatures over the past century.
Melting Glaciers and Ice Sheets
Glaciers and polar ice sheets are melting at an alarming rate, contributing to sea level rise.
Sea Level Rise
The average global sea level is rising due to thermal expansion of ocean water and melting glaciers.
Changes in Precipitation Patterns
Global warming is altering precipitation patterns, leading to more extreme weather events like heat waves, droughts, and floods.
Ocean Acidification
Increased carbon dioxide dissolving in the oceans makes them more acidic, harming marine ecosystems.
Greenhouse Gas Emissions
The burning of fossil fuels (coal, oil, natural gas) is the primary source of human-caused greenhouse gas emissions, particularly carbon dioxide.
Deforestation
Forests absorb carbon dioxide, so deforestation contributes to higher atmospheric concentrations.
Other Human Activities
Industrial processes, agriculture, and waste management also release greenhouse gases.
Increased Temperatures
Rising temperatures can lead to heat waves, droughts, and more intense storms.
Changes in Precipitation Patterns
Global warming disrupts weather patterns, leading to increased variability in precipitation, with both floods and droughts becoming more common.
Sea Level Rise
Rising sea levels threaten coastal communities and ecosystems.
Extreme Weather Events
Global warming is expected to increase the frequency and intensity of extreme weather events.
Temperature in London
Average annual temperature in London is about 1-2°C higher than surrounding rural areas.
Heatwaves in London
Heatwaves are becoming more frequent and intense. For example, in July 2019, central London reached a record high of 38.7°C, exceeding rural areas by as much as 5°C.
Humidity in London
The urban environment can trap moisture due to reduced ventilation and higher temperatures. However, the overall impact on humidity in London is complex and depends on factors like wind patterns and precipitation.
Precipitation in London
The urban heat island effect can influence precipitation patterns. Rising temperatures can lead to increased convection and potentially more intense downpours, but also contribute to unpredictable changes in overall precipitation amounts. While summers may see drier periods, heavy rainfall events can cause flash flooding.
Winds in London
Buildings and tall structures can disrupt natural wind patterns within the city. This can lead to reduced air circulation and exacerbate the heat island effect, particularly in densely built-up areas.
Heat island at night
The effects of the urban heat island are most pronounced during nighttime hours, as rural areas cool down more readily.
Global impact
The impacts of human activity on climate are not limited to London. Similar effects can be observed in most major cities around the world.
Location - Heat island
Research suggests Central London, particularly areas with high building density like the City of London and Westminster, experience the most significant heat island effect.
Location - Green spaces
Areas with larger green spaces, like Richmond upon Thames in southwest London, tend to have lower average temperatures.
