Earth's Spheres Interactions and Geography

Introduction to Physical Geography

• Physical Geography studies spatial and temporal patterns of Earth's physical environment. This includes energy, air, water, weather, climate, landforms, soils, animals, plants, and the Earth itself.
• Earth's Four Subsystems (Spheres) are:
  • Lithosphere: This is the solid Earth, which includes mountains, soils, tectonic plates, volcanoes, and faults
  • Atmosphere: Consists of weather, climate, greenhouse gases, aerosols, and water in various forms.
  • Hydrosphere: Comprises oceans, rivers, lakes, streams, glaciers, snow, and ice.
  • Biosphere: Includes all living things like plants, animals, bacteria, humans, carbon, and agriculture.

Interactions Between the Spheres

• Volcanic eruptions (lithosphere) impact temperature, precipitation, and atmospheric chemistry (atmosphere & hydrosphere).

• Climate change impacts ecosystems and biodiversity within the biosphere.

• Water cycles (hydrosphere & lithosphere) shape landscapes and influence climate patterns.

• The role of water in geography includes shaping landscapes, influencing life distribution, and regulating climate.

• Alexander von Humboldt (1769–1859) developed early theories explaining Earth's physical variations and mapped climate and vegetation across different regions.

• Latitude measures distance north or south from the Equator.

• Longitude measures distance east or west from the Prime Meridian.

• The Earth is divided into Northern, Southern, Eastern, and Western Hemispheres.

• Great Circles: the shortest distance between two points on Earth follows a path.

• The sun, Earth's primary energy source, influences the climate and shapes the physical environment.

• Energy = a property of every physical system, including anything with mass that occupies space.

• The energy provided by the sun is in the form of Electromagnetic Radiation.

  • The Sun generates energy through continuous nuclear reactions where lighter elements (Hydrogen) combine to form heavier elements (Helium), releasing excess energy.
  • Photons leave the sun (and all objects) and travel through space in waves at the speed of light.

• The sun is ~90 million miles from Earth, positioned at the center of our Solar System

• Joule (J) = The energy to lift a small apple (100g) vertically 1 meter.

• Watt (W) = 1 J per second and measures the rate ("flux") of energy entering/leaving a system

Equator v Poles

• The equator gets more direct sunlight.
• The poles receive sunlight at a lower angle, spreading energy over a larger area (less intense solar radiation).
• Solar altitude angle represents the angle between the sun and the horizon
  • Higher latitude= the smaller the solar angle because sun is on the horizon
  • A higher Solar Altitude Angle= more direct sunlight and higher temperatures.
• The Plane of the Ecliptic describes all planets in the Solar System revolving counter-clockwise around the sun in the same plane. Earth's axis tilts 23.5° off being perpendicular to ecliptic plane
  • Earth's tilt causes seasons by changing how directly sunlight hits throughout the year.

Solstices v Equinoxes

• June 21-22: Summer Solstice occurs in the Northern Hemisphere with the longest day, sun over 23.5°N, marking the start of summer. Winter Solstice happens in the Southern Hemisphere which has the shortest day and colder temps, marking the start of winter.
• December 21-22: Winter Solstice happens in the Northern Hemisphere with the shortest day, and sun over 23.5°S, marking the start of winter. Summer Solstice occurs in the Southern Hemisphere with the longest day and warmer temperatures, marking the start of summer.
• March 21-22: Spring Equinox occurs in the Northern Hemisphere, and Autumn Equinox in the Southern Hemisphere (equal day/night, with sun over the Equator and seasonal transition).
• September 21-22: Autumn Equinox occurs in the Northern Hemisphere, and Spring Equinox in the Southern Hemisphere (equal day/night, with sun over Equator, and seasonal transition).
• Winter is colder due to sunlight hitting at a lower angle, spreading energy and reducing heat intensity. Summer has a larger solar angle with concentrated solar energy.
• 23.5°N latitude has the highest solar altitude angle during the Northern Hemisphere Summer Solstice b/c 90° solar angle
• Solar Declination Latitude refers to the latitude where the sun is directly overhead at noon on any given day.
• Solar declination latitude (December 21-22) equals 23.5°S during the Northern Hemisphere Winter Solstice/ Southern Hemisphere Summer Solstice. 66.5°S is defined as the Antarctic Circle
• Solar Declination Latitude (June 21-22) is 23.5°N during the Northern Hemisphere Summer Solstice/ Southern Hemisphere Winter Solstice. 66.N°S is the Arctic Circle.
• Tropics extend from (23.5°N to 23.5°S), receiving intense solar radiation year-round. During June the North Pole experiences 24 hours of daylight, maximizing solar input and receiving the most solar radiation on the planet.
• To see 24 hours of sunlight on the Summer Solstice, you have to travel to 66.5°N (Arctic Circle) or 66.5°S (Antarctic Circle)
• Permafrost describes permanently frozen ground, with low solar altitude angle/intensity in the Arctic resulting in a cold condition and frozen soil. Permafrost stores substantial carbon, which is released when it thaws.

Earth's Balance

• The Electromagnetic Spectrum contains:
  • Shortwave radiation which is most intense.
  • Longwave radiation which is the least intense.
• Photons travel at the speed of light through waves.
• Wavelength refers todistance between two waves of electromagnetic radiation (measured in micrometers (μm)).
• Only a few wavelengths are visible. Objects need to be extremely hot to emit electromagnetic radiation that is in the visible part of the spectrum
• Everything emits electromagnetic radiation.
  • Rule #1: Hotter objects emit shorter wavelengths.
  • Rule #2: The shorter the wavelengths, the more intense the radiation.
• The sun emits shortwave radiation (covering visible light, ultraviolet), and Earth emits longwave radiation (infrared). Whether a person emits or reflects infrared light depend on the light source. A person reflects visible light from an external source, making them visible in the left image. In the infrared image, they emit infrared radiation due to body heat, appearing bright, and the trash bags are transparent to photons in in the infrared portion of the spectrum. The glasses are okay to infrared light but transparent to visible light. A human body emits infrared radiation, but only reflects visible light- this also applies to greenhouse gases.
• Movement from atoms that are warmer vibrates at a faster rate.
• If constantly bombarded by solar radiation the earth will emit longwave radiation back into outer space to remain at an equibiurm temperature.
• the earth must send radiation to outer space as fast as it comes in, to maintain a stable temperature. The rate of photons receiving = rate of photons exiting. if not, temperature will change
  • Shortwave radiation that is reflected to outer space
  • Long wave radiation admitted to outer space
• Radiative equilibrium describes the concept of incoming solar (shortwave) radiation equaling the amount of radiation sent back to outer space (reflection + longwave emission) to maintain the Earth's stable temperature.
  • Solar (shortwave) radiation entering the atmosphere = longwave radiation emitted by Earth + shortwave radiation reflected to space This is done in two ways
    • Solar radiation is reflected off a surface
    • The rest is absorbed into Earth and emits long wave radiation back to outer space
• Emission refers to objects emitting energy by sending photons outward to lose energy and cool
• Reflection refers to objects bouncing photons away without absorbing so the energy status and temperature of the object is unaffected.
• Absorption refers to objects absorbing photons, increasing the energy status of the object and temperature.
• Albedo quantifies the fraction of incoming solar radiation that is reflected back into space.
  • High albedo = More reflection (e.g., ice, snow).
  • Low albedo = More absorption (e.g., oceans, forests).
  • Earth's planetary albedo averages ~30

Solar Radiation

• 70% of solar radiation enters the earth. It's absorbed by the surface and atmosphere and later emitted as longwave radiation.
• Incoming solar at the top of atmosphere totals (342 W/m^2). Longwave radiation the earth must emit to outer space to maintain a stable temperature is (239 W/m2)
• High albedo occurs with Ice caps, deserts, clouds, poles, and low albedo occurs with oceans, forests, dark surfaces.

Temperature

• Temperature changes the amount of radiation emitted from the earth's surface depending on whether its cold or hot.
• Temperature (cold) =less intense radiation (less longwave radiation + longer waves).
• Temperature (hotter)= more long wave radiation because has to emit long wave radiation to cool off
• Earth emits more longwave radiation through its surface than it ultimately emits to outer space becauseThe atmosphere is transparent for short wave radiation but opaque for long wave radiation due to the greenhouse effect.
• Most emitted longwave radiation from greenhouse gas molecules is re-absorbed and emitted in all directions which warms the surface and lower atmosphere.
  • The sun's shortwave radiation passes through the atmosphere and heats the Earth's surface.
  • The Earth emits longwave radiation upward.
  • Greenhouse gases in the atmosphere absorb the longwave radiation from earth and send some downward and some into space. This slows the rate at which earth can cool off by emitting longwave radiation to space Bombardment from downward longwave radiation causes earth's surface to warm, causing earths' surface to emit more longwave radiation upwards (hotter objects emit more radiation).
• As longwave emission from earth's warming surface continues to increase, more longwave radiation can escape to space despite the fact that most radiation emitted from the surface continues to be absorbed by greenhouse gases and when radiative equilibrium is achieved warming stops
• Without the Greenhouse Effect, Earth's temperature is ~ -15°C (5°F). Instead, the Greenhouse Effect keeps it at ~18°C (65°F).
• John Tyndall in the 1850s, detected heat-trapping effects of gases
• Greenhouse gases:
  • Water Vapor (H2O): is the most abundant greenhouse gas.
  • Carbon Dioxide (CO2): is the major contributor to human-caused global warming.
  • Methane (CH4): is a more powerful, but less abundant, greenhouse gas.
  • Ozone (O3): absorbs UV radiation and also acts as a greenhouse gas.
• The greenhouse effect works with with the ability of a gas molecule to absorb electromagnetic radiation and molecules like greenhouse gases vibrate in multiple directions and frequencies, making them very good absorbers of longwave radiation
• Humans are rapidly increasing the greenhouse gas concentration, pulling carbon out of Earths crust and burning for energy

Local Energy Balances

• Net Radiation (Rnet) is the rate of incoming radiation minus outgoing radiation (watts per square meter, W/m²). It needs to be at zero to be at equilibrium
  • Earth's is close to zero, but not of green house gases
  • Poles display a constant negative net radiation
• Rnet absorbed at the earth's surface is absorbes +106 W/m² because the surface absorbs much more radiation than it emits. Energy in the atmosphere is transferred through evaporation, latent heat flux, and sensible heat flux.
• The net radiation at the bottom of the pot is very positive, but evaporation carries energy away, cooling the surface.
• Evaporation needs energy from the surrounding environment through the energy being carried away by water vapor.
• To convert liquid water into water vapor heat transfers to the water that then floats into the atmosphere. This COOLS the evaporation site
• Latent Energy stores energy in water vapor molecules energy associated with water phase change which uses A LOT of energy.
• Hydrogen bonding causes molecules to attract to each other that makes the molecules want to stick together makes it difficult to raise temperature
• Specific Heat measures liquid water, its the energy required to heat 1 kg by 1 °C: 4186 J/(kg x °C)
• Oceans provide a continuous water source for evaporation, transferring large amounts of energy to the atmosphere causing Latent heat fluxes high over the ocean. Over dry land (e.g., deserts) there is little water available for evaporation which explains why you would expect latent heat fluxes to be lowest
• Summer generates the most solar energy making it What time of year Latent heat fluxes the highest
• Condensation: is when water vapor molecules turn back into the liquid phase and releases energy into the atmosphere, causing warming and wind.
• Sensible Heat Flux describes the exchange of energy through direct contact between two things, depending in temperature, in the atmosphere
• It is hard to change the temperature of the ocean. If you put energy on the surface, that will go to evaporation, which causes cooling which is the reason Upward sensible fluxes generally higher over continents than the ocean?
• Summertime = the surface is hotter which translates to the time of year that Upward sensible fluxes are the most positive
• heat is being transferred from the atmosphere to the surface, rather than from the surface to the atmosphere. This occurs when Upward sensible flux is negative because the surface is cooler than the air above it, causing a downward heat transfer
• Energetic balance describes the rate of incoming energy that equals the outgoing energy when radiative equilibrium is reached

Transition from Liquids to Gases

• The transfer from Liquids to Gases occurs through Shortwave absorbed = Longwave emitted + Upward latent heat flux + Upward sensible heat flux.
• Liquid to a gas is evaporation when a liquid turns to a gas and then warms (gains energy) where it starts vibrating and distancing itself from its liquid molecules leading it to the atmosphere

Vapor Phase v Liquid Phase

• Vapor phase translates to more energy per molecule, molecules moving fast. Liquid phase shows less energy per molecule and molecules move at a slow rate. What is condensation? The transition from gas (vapor) to liquid occurs when water vapor turns liquid when it cools (loses) which causes it congeal
• If condensation exceeds evaporation this is called net condensation which means the air is staturated, otherwise if the are is unsaturated then theres too much evaporation
• Specific Humidity is a description of the fraction of air that made of vapor molecules what is vapor Pressure? The contribution of water vapor to atmospheric pressure (measured in hectopascals, hPa)
• Increase evaporation from the water molecules comes from adding energy and reducing the presure, known as the reduction of vapor pressure known as Saturated Vapor Pressure. This pressure is from the water vapor at which the water is completely satuated. and at this units: hectopascals (hPa). The warmer the air, the higher the saturation vapor pressure.
• Warmer air is able to "hold” more water vapor than cooler air because water molecules bind to each other

Temperate, Clausius-Clapeyron and Humidity

• The Claussius-Clapeyron relationship states The exponential shape means that as air temperature rises, amount of vapor that air can accomadate rises exponentially -Air temperature: 25°C -Vapor pressure: 16 hPa

• Dew point. The temperature at which the air with a specific humidity saturates

• Oceans provide an umlimited supply of atoms to form for saturation and oceans provide an umlimitedsupply of atmosphere which mean the dew point is lower over contientns than in the ocean regions

• In order to bring the ari over to condensation you can add humidity. In order to determine Humidity use elative Humidity: The amount of water vapor in the air being expressed as a percentage of the amount needed for saturation Mixing air in different temperatures helps create fog, which is what The warnm aif of your breath is when its cold outside

• As temperature increases the atmopshere gets saturated and this affects how water travels More weather means when storms come they are going to be heavier due the high presure which results in deadly outcomes.

• Increased flooding, deadly storms causes problems Seawalls are built as a counter measure.

Atmosphere

• Troposphere averages 80-85% of the amtosphere
• Stratosphere averages 15-20% 0f atmopshere
• Mesosphere averages less than 1%
• Thermosphere averages less the 1%, and Why does pressure increase exponentially as altitude in the atmosphere deacreases but doesnt occur the sane im the oceans?
  • becuase gas is compressaible, the molecules can squish against one another versus atoms are uncompressionable. High compression due to the squish of hte atoms that cause the temperature to increase in atmspheric density.
• Convection-Rising air heat driven expansion,

Expansion

• Surface heats then the molecules expand and become less dense causing the atoms to create atmosphere as they left the ground, Atmosphere and pressure are low in the atmosphere which creates the gradiant which affects how convection creates surface winds, The different in presure affect how pressure graditant works.

Land vs Sea

• During the Day Sea Breese will cause Ocean to be cooler and land warmer and air will be closer but at night the effect is reversed with land the cool and wind blow the side froms the side the ocean The differeance usually are very great during night than day, In florida the ocean breeze cominf from two directions, The overation is very easy as the air molecules is to expands but its also costs ALOT energy, In tropica are so much convetive persipation? This is bcause thier alot more hot that can travel throught. Because the Tropiczone stretches

Convergence Zones

• Tropical area is giant and its very convetive , where surface pressure the itcz lead to the pressure because of humdits

Effects of weather

• Atmosphere will increase altitude becuse the weather become variable, Coriolis Effect

• Effect the force due to earth’s ration,The earth’s spin prevents from from reaching the surface, the Coriolis defelct moving weather due earth rotation

Wind rotation

• Northen hemi- All moving defelct to right,
• Southen Hemip- All movig deflect to the left , The coriolis affects what happens to global circulation
• tropical tradewinds= blow east to to west
• Middle latitude blows west yo east. What is the reason that Hadicy Cells happens, What about subsides subsides, sinking and warming

Convergence

Water is very warm and orginate as evation that has alot moist water.

Climate

• Tropes relatively comfrotble bwetween sub and pole latitudes,When miralited westerlies is in the weather
• Rossely moves polar wind and it causes weather to collide

What happens weather collide?

• Wind will collide causing rotation and then cold airmass smashes inot warm
• Weather will enhance the effect of high of cold, surface presured will cause a great conveyor belt to form and continuous stream to make it warmer but then cold will start to flow back

Sea temp

• Temprature high specific- it takes takes longter for water to decrease
• When ocean is more dence you can spread the energy -Vertical mining.
• The east continent is usually more summer than west, west contains very cold wether is more temperate then the east. Alot of them depends high the itcz. As long itcz has heat as energy it takes the most and it gives flood rest

Lapse Air

• When the air is drier its much hotter than the most, Is it ever the same everywhere? What causes the rate of cooling is expand and high and does what affects if it reduces the humidity
  • Sinking and drying is hot that effects what is. This creates a high surface tension causing subsides leading tp tropical dry desrets

Mountains

• What happends when mountanis form, where water it falls? - Orographic lifting, high elevation of clouds that increase the amount weather,
• What heppens when wind hits the mountain? - Sinking and it warmer, Wind at which wind at the storm will be.What is the effects does is does this the

Ocean

• Water will move due the effect of Curiolis effects whcih spin when to center and effect if the wind. Water moves from traffic the the weather is more from south to north. The water sinking, is the water sinking, and sinking because of that.

Water molecules flow and causes

• Water sinks the temp, salinity, and denses,The shape of concience causes what The ocean causes air be be water molecules,

Tropics vs Australia

• Water gets heated an water is hot an the east or australi and the the the ocean current the water will move but is water the surface area where water causes this is the. This helps keep the east coast warm. El Nino is caused the the ocean

Explore the interactions between Earth's spheres (lithosphere, atmosphere, hydrosphere) and geographic concepts. Questions cover topics such as drought impacts, latitudinal positions, great circle paths, cloud cover effects, deforestation consequences, ocean temperature influences, polar daylight, and more.