Class 11 : Geography (In English) – Lesson 8. Solar Radiation, Heat Balance and Temperature
EXPLANATION & SUMMARY
📘 1. Detailed Explanation
🌞 Introduction
🌍 The Earth’s climate system and all forms of life depend fundamentally on solar energy, which is the primary source of heat and light. This solar energy reaches our planet in the form of radiation and influences atmospheric processes, weather, climate patterns, and the functioning of ecosystems. Understanding how solar radiation is received, distributed, balanced, and transformed into heat is crucial to comprehend global temperature variations and climatic systems.
🌤️ The Earth neither produces its own significant energy nor stores it permanently — instead, it continuously receives solar energy and loses it back to space. The balance between incoming and outgoing radiation determines the Earth’s heat budget, which in turn influences global temperature, weather patterns, and long-term climatic changes.
☀️ Solar Radiation
🌞 Solar radiation refers to the energy emitted by the Sun in the form of electromagnetic waves. It travels through space at the speed of light (~300,000 km/s) and reaches Earth in about 8 minutes and 20 seconds.
🌟 Composition of Solar Radiation
Solar radiation consists of a spectrum of electromagnetic waves, categorized by their wavelength:
☀️ Ultraviolet radiation (UV): Short wavelengths, most absorbed by the ozone layer.
🌤️ Visible light: Medium wavelengths (0.4–0.7 μm), the most significant part of solar radiation (~46%).
🌡️ Infrared radiation: Long wavelengths (>0.7 μm), mainly responsible for heating the Earth’s surface.
🪐 Solar Constant
📏 The solar constant is the average amount of solar radiation received per unit area at the top of Earth’s atmosphere on a surface perpendicular to the Sun’s rays. Its value is about 1.94 cal/cm²/min or 1367 W/m².
☀️ Insolation
🌍 Insolation (incoming solar radiation) refers to the solar energy received by the Earth’s surface per unit area. It varies significantly due to several factors that influence how much solar energy reaches different parts of the Earth.
🌎 Factors Affecting Insolation
📊 The distribution of insolation is influenced by the following factors:
🌐 Latitude:
Equatorial regions receive vertical rays and thus more insolation.
Polar regions receive slanting rays and less energy.
🪐 Angle of Incidence:
The greater the angle, the more concentrated the solar energy.
At low angles (near poles), energy is spread over a larger area.
🌞 Duration of Sunshine:
Longer daylight hours = more insolation.
🌫️ Atmospheric Transparency:
Clouds, dust, and water vapor absorb or scatter radiation, reducing insolation.
🏔️ Altitude:
Higher altitudes receive more insolation due to thinner atmosphere.
🌊 Earth’s Distance from the Sun:
Slight variations due to elliptical orbit (~3.3% more insolation at perihelion than aphelion).
☀️ Distribution of Insolation
🌍 Maximum insolation occurs in tropical deserts due to clear skies and high solar angles.
🌨️ Minimum insolation occurs near poles due to low angles and longer atmospheric paths.
🌊 Oceans absorb less insolation than land but distribute it more evenly due to water’s high specific heat.
🌤️ Heating and Cooling of the Atmosphere
The Earth’s atmosphere is heated indirectly — most solar radiation is absorbed by the Earth’s surface, which then radiates energy back into the atmosphere as terrestrial radiation.
☀️ Mechanisms of Atmospheric Heating
🌞 Radiation:
Transfer of energy in the form of electromagnetic waves.
Solar radiation heats the Earth’s surface.
🌍 Conduction:
Transfer of heat from molecule to molecule.
Surface heats the air in direct contact.
🌡️ Convection:
Vertical movement of air due to heating.
Warm air rises, cool air sinks, creating convection currents.
🔄 Advection:
Horizontal transfer of heat by winds.
Responsible for warm and cold air movements.
☀️ Heat Budget or Earth’s Energy Balance
🌎 The heat budget is the balance between incoming solar radiation and outgoing terrestrial radiation. For the Earth to maintain a stable temperature, the total incoming energy must equal the total outgoing energy.
☀️ Energy Distribution
Out of 100 units of solar radiation:
☁️ ~35 units are reflected back to space (albedo).
🌊 ~51 units are absorbed by the Earth’s surface.
🌫️ ~14 units are absorbed by the atmosphere.
Outgoing radiation:
🌍 Earth radiates ~51 units back as longwave radiation.
🌫️ Atmosphere and clouds reradiate ~48 units.
☀️ Total outgoing = total incoming (~100 units).
🌐 Albedo
🌟 Albedo is the reflectivity of a surface — the percentage of incoming solar radiation reflected back without absorption.
❄️ Fresh snow: ~80–90%
🌊 Oceans: ~5–10%
🌿 Forests: ~10–15%
🏙️ Earth’s average albedo: ~30–35%
Higher albedo = less heat absorption.
🌡️ Terrestrial Radiation
🌍 The Earth absorbs solar radiation and reradiates it as longwave infrared radiation. This outgoing radiation interacts with atmospheric gases like CO₂ and water vapor, forming the greenhouse effect — trapping heat and maintaining Earth’s temperature around 15°C.
Without this natural greenhouse effect, Earth’s temperature would be about –18°C, making life impossible.
☁️ Temperature
🌡️ Temperature refers to the degree of hotness or coldness of the atmosphere. It is a direct result of the balance between incoming solar radiation and outgoing terrestrial radiation.
🌡️ Factors Influencing Temperature Distribution
🌐 Latitude:
Equatorial regions are warmer; polar regions are colder.
🏔️ Altitude:
Temperature decreases with height (~6.5°C per 1000 m).
🌊 Distance from Sea:
Coastal areas have moderate temperatures (maritime climate).
Interiors experience extremes (continental climate).
🌦️ Ocean Currents:
Warm currents raise temperatures; cold currents lower them.
☀️ Cloud Cover:
Clouds reduce daytime temperature but trap heat at night.
🌬️ Winds and Air Masses:
Transport warm or cold air, modifying temperature.
🏔️ Slope and Aspect:
South-facing slopes (Northern Hemisphere) receive more sunlight and are warmer.
🌡️ Vertical Distribution of Temperature
In the troposphere, temperature decreases with altitude at an average lapse rate of 6.5°C per 1000 m.
📉 Reasons for this decrease:
Lower density of air at higher altitudes
Greater distance from Earth’s surface (main source of heat)
Expansion and cooling of rising air
🗺️ Horizontal Distribution of Temperature
Temperature varies across the Earth’s surface due to latitude, altitude, ocean currents, and continentality. Two important lines help in understanding temperature distribution:
🌍 Isotherms: Lines connecting points of equal temperature.
🌎 Thermal Equator: Imaginary line connecting areas of maximum temperature, shifting seasonally.
🌍 Inversion of Temperature
🌡️ Temperature inversion occurs when temperature increases with height instead of decreasing. It typically occurs under calm, clear conditions at night when the ground cools rapidly, cooling the air close to the surface.
📍 Types:
🌙 Radiation Inversion: Due to nighttime cooling.
🌄 Valley Inversion: Cold air trapped in valleys.
🌬️ Advection Inversion: Warm air moves over a cold surface.
📊 Effects:
Suppression of vertical air movement
Trapping of pollutants near the ground
🌐 Global Temperature Patterns
🌏 Temperature distribution shows distinct patterns:
🌞 Equatorial Regions: High temperatures (~27–30°C).
🌤️ Subtropics: Slightly lower due to descending air.
🌊 Mid-Latitudes: Moderate temperatures with seasonal variation.
❄️ Polar Regions: Extremely low temperatures (~–30°C or lower).
📈 Seasonal shifts in isotherms are more prominent in continental interiors and less noticeable over oceans due to water’s moderating effect.
🌡️ Heat Budget and Climate Change
🌍 Human activities have disturbed the Earth’s heat budget, mainly through greenhouse gas emissions. This leads to enhanced greenhouse effect and global warming.
📊 Consequences:
Rising global temperatures
Melting ice caps and rising sea levels
Extreme weather events
Shifts in climatic zones
📉 Solutions:
Reducing fossil fuel use
Reforestation
Renewable energy adoption
International agreements (Paris Climate Accord)
🧪 Importance of Solar Radiation and Temperature
Understanding solar radiation, heat balance, and temperature is essential for:
🌦️ Predicting weather and climate patterns
🌾 Planning agriculture based on temperature zones
🏙️ Designing buildings for thermal comfort
🪐 Studying global climate change and mitigation strategies
📚 2. Summary (~300 Words)
Solar radiation is the primary source of Earth’s energy, reaching the planet as electromagnetic waves. The amount received (insolation) varies by latitude, angle of incidence, duration of sunshine, and atmospheric conditions. The Earth’s surface absorbs solar energy and reradiates it as terrestrial radiation, heating the atmosphere indirectly.
The heat budget represents the balance between incoming solar energy and outgoing terrestrial radiation. Of the total radiation received, about 35% is reflected (albedo), 51% absorbed by the surface, and 14% absorbed by the atmosphere. The greenhouse effect maintains Earth’s average temperature, but excess greenhouse gases lead to global warming.
Temperature, the measure of atmospheric heat, is influenced by latitude, altitude, ocean currents, and distance from the sea. It decreases with altitude at an average lapse rate of 6.5°C per 1000 m but can invert under certain conditions. Horizontal and vertical distributions of temperature shape weather and climate patterns globally.
Understanding solar radiation, heat balance, and temperature is vital for predicting weather, planning agriculture, designing human habitats, and addressing climate change. A stable energy balance is essential to sustain Earth’s environment and support life.
⚡ 3. Quick Recap (~100 Words)
Solar radiation powers Earth’s climate system. Insolation varies with latitude, angle, and atmospheric conditions. The Earth absorbs solar energy and reradiates it as longwave terrestrial radiation, forming the greenhouse effect and maintaining a stable temperature. The heat budget balances incoming and outgoing radiation. Temperature, influenced by latitude, altitude, and ocean currents, decreases with altitude but can invert under specific conditions. Its distribution shapes global weather and climate. Human activities are altering the heat balance, causing global warming. Understanding these processes is key to managing environmental changes and sustaining life on Earth.
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QUESTIONS FROM TEXTBOOK
📘 Questions and Answers (Questions and Answers Together)
✨ 1. Multiple Choice Questions (MCQs)
🔴 Q1: The sun is directly overhead at noon on 21st June at:
🟢 (a) The equator
🔵 (b) 23.5° S
🟡 (c) 23.5° N
🟣 (d) 66.5° N
✅ Answer: 🟡 (c) 23.5° N
🟠 Q2: In which one of the following cities, are the days the longest?
🟢 (a) Thiruvananthapuram
🔵 (b) Chandigarh
🟡 (c) Hyderabad
🟣 (d) Nagpur
✅ Answer: 🔵 (b) Chandigarh
🟡 Q3: The atmosphere is mainly heated by:
🟢 (a) Short wave solar radiation
🔵 (b) Reflected solar radiation
🟡 (c) Long wave terrestrial radiation
🟣 (d) Scattered solar radiation
✅ Answer: 🟡 (c) Long wave terrestrial radiation
🟣 Q4: Make correct pairs from the following two columns:
Term Meaning
(i) Insolation (c) The incoming solar radiation
(ii) Albedo (d) The percentage of visible light reflected by an object
(iii) Isotherm (b) The lines joining the places of equal temperature
(iv) Annual range (a) The difference between the mean temperature of the warmest and coldest months
✅ Answer: i → c, ii → d, iii → b, iv → a
🔵 Q5: The main reason that the earth experiences highest temperatures in the subtropics in the northern hemisphere rather than at the equator is:
🟢 (a) Subtropical areas tend to have less cloud cover than equatorial areas
🔵 (b) Subtropical areas have longer day hours in the summer than the equatorial
🟡 (c) Subtropical areas have an enhanced “greenhouse effect” compared to equatorial areas
🟣 (d) Subtropical areas are nearer to the oceanic areas than the equatorial locations
✅ Answer: 🟢 (a) Subtropical areas tend to have less cloud cover than equatorial areas
✏️ 2. Short Answer Questions (About 30 Words Each)
🔴 Q1: How does the unequal distribution of heat over the planet earth in space and time cause variations in weather and climate?
🌱 Answer: Unequal heating causes differences in temperature and pressure, leading to atmospheric circulation, wind patterns, ocean currents, and precipitation. These variations drive weather changes and long-term climate differences.
🟠 Q2: What are the factors that control temperature distribution on the surface of the earth?
🌱 Answer: Major factors include latitude, altitude, ocean currents, distance from the sea, land-sea distribution, prevailing winds, and cloud cover. These factors interact to create regional temperature variations.
🟣 Q3: In India, why is the day temperature maximum in May and why not after the summer solstice?
🌱 Answer: Maximum heating occurs in May because the ground absorbs heat quickly before the monsoon arrives. After the solstice, cloud cover and rainfall reduce incoming solar radiation, lowering temperatures.
🔵 Q4: Why is the annual range of temperature high in the Siberian plains?
🌱 Answer: Siberia’s continental location, high latitude, and lack of maritime influence cause very cold winters and warm summers, resulting in a large annual temperature range.
📜 3. Long Answer Questions (About 150 Words Each)
🔴 Q1: How do the latitude and the tilt in the axis of rotation of the earth affect the amount of radiation received at the earth’s surface?
🌱 Answer: Latitude determines the angle of the sun’s rays — near the equator, sunlight is direct and concentrated, causing higher temperatures. At higher latitudes, sunlight is oblique and spread over a larger area, reducing intensity. The Earth’s axial tilt (23.5°) causes seasonal variation in solar radiation. When a hemisphere tilts towards the Sun, it experiences summer with longer days and higher solar input. The opposite hemisphere receives less radiation and experiences winter. This tilt also causes variations in the length of day and night, influencing temperature and climate patterns globally.
🟢 Q2: Discuss the processes through which the earth-atmosphere system maintains heat balance.
🌱 Answer: Earth’s heat balance involves:
Incoming solar radiation (insolation): Shortwave energy from the Sun absorbed by the surface.
Outgoing terrestrial radiation: Longwave radiation emitted from Earth back into space.
Absorption and scattering: Atmosphere absorbs part of solar radiation and scatters some back to space.
Latent heat transfer: Evaporation and condensation transport energy.
Convection and conduction: Heat transfer through air movement and contact.
These processes maintain equilibrium: the Earth absorbs as much energy as it radiates, ensuring a relatively stable climate. Disturbances in this balance lead to climate changes.
🟣 Q3: Compare the global distribution of temperature in January over the northern and the southern hemisphere of the earth.
🌱 Answer: In January, the northern hemisphere experiences winter, with low temperatures over continents and slightly higher temperatures over oceans. Cold air masses dominate regions like Siberia and Canada. The southern hemisphere, tilted towards the Sun, has summer with higher temperatures, especially over continents like Australia and South America. The thermal equator shifts southward due to this seasonal contrast. Temperature gradients are sharper in the northern hemisphere due to greater landmass, whereas the southern hemisphere shows more uniform temperatures because of larger oceanic areas.
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OTHER IMPORTANT QUESTIONS FOR EXAMS
🌏 Section A — Multiple Choice Questions (1 mark each)
🔵 Question 1: What is the primary source of energy for Earth’s atmosphere?
🟢 1️⃣ Solar radiation
🔴 2️⃣ Geothermal energy
🟡 3️⃣ Volcanic heat
🔴 4️⃣ Ocean currents
✔️ Answer: Solar radiation
🟡 Question 2: The total amount of solar energy received per unit area at the outer edge of Earth’s atmosphere is known as:
🟢 1️⃣ Solar constant
🔴 2️⃣ Insolation
🟡 3️⃣ Albedo
🔴 4️⃣ Heat budget
✔️ Answer: Solar constant
🔴 Question 3: The average value of the solar constant is approximately:
🟢 1️⃣ 2.04 cal/cm²/min
🔴 2️⃣ 1.94 cal/cm²/min
🟡 3️⃣ 1.94 J/cm²/min
🔴 4️⃣ 0.94 cal/cm²/min
✔️ Answer: 1.94 cal/cm²/min
🟢 Question 4: The percentage of solar radiation reflected back into space by Earth’s surface and atmosphere is called:
🟢 1️⃣ Albedo
🔴 2️⃣ Insolation
🟡 3️⃣ Conduction
🔴 4️⃣ Convection
✔️ Answer: Albedo
🔵 Question 5: Which of the following factors does NOT influence insolation?
🟢 1️⃣ Solar constant
🔴 2️⃣ Earth’s distance from the Sun
🟡 3️⃣ Ocean currents
🔴 4️⃣ Angle of incidence
✔️ Answer: Ocean currents
🟡 Question 6: The atmosphere is mainly heated by:
🟢 1️⃣ Direct absorption of solar radiation
🔴 2️⃣ Radiation from Earth’s surface
🟡 3️⃣ Solar convection
🔴 4️⃣ Reflection of sunlight
✔️ Answer: Radiation from Earth’s surface
🔴 Question 7: The process of heat transfer by direct contact of molecules is called:
🟢 1️⃣ Conduction
🔴 2️⃣ Convection
🟡 3️⃣ Radiation
🔴 4️⃣ Scattering
✔️ Answer: Conduction
🟢 Question 8: Which of the following is the most effective method of heat transfer in the atmosphere?
🟢 1️⃣ Convection
🔴 2️⃣ Conduction
🟡 3️⃣ Radiation
🔴 4️⃣ Absorption
✔️ Answer: Convection
🔵 Question 9: The balance between incoming and outgoing radiation is known as:
🟢 1️⃣ Heat budget
🔴 2️⃣ Insolation
🟡 3️⃣ Solar balance
🔴 4️⃣ Temperature inversion
✔️ Answer: Heat budget
🟡 Question 10: The process by which Earth radiates heat energy back to space is called:
🟢 1️⃣ Terrestrial radiation
🔴 2️⃣ Insolation
🟡 3️⃣ Reflection
🔴 4️⃣ Refraction
✔️ Answer: Terrestrial radiation
🔴 Question 11: What is the approximate average temperature of the Earth’s surface?
🟢 1️⃣ 15 °C
🔴 2️⃣ 25 °C
🟡 3️⃣ 10 °C
🔴 4️⃣ 30 °C
✔️ Answer: 15 °C
🟢 Question 12: Which factor causes variation in temperature between equator and poles?
🟢 1️⃣ Angle of solar incidence
🔴 2️⃣ Ocean salinity
🟡 3️⃣ Earth’s tilt
🔴 4️⃣ Rotation of Earth
✔️ Answer: Angle of solar incidence
🧭 Section B — Short Answer Questions (15–20 words each)
🔵 Question 13: What is insolation?
🟢 Answer: Insolation is the total amount of solar radiation received per unit area of Earth’s surface in a given time.
🟡 Question 14: Define albedo.
🟢 Answer: Albedo is the percentage of incoming solar radiation reflected by Earth’s surface and atmosphere back into space.
🔴 Question 15: What is terrestrial radiation?
🟢 Answer: Terrestrial radiation is the longwave radiation emitted by Earth’s surface after absorbing solar energy.
🟢 Question 16: What is the heat budget?
🟢 Answer: The heat budget is the balance between incoming solar radiation and outgoing terrestrial radiation, maintaining Earth’s temperature.
🔵 Question 17: What is conduction?
🟢 Answer: Conduction is the transfer of heat through direct contact between molecules without actual movement of the substance.
🟡 Question 18: Define convection.
🟢 Answer: Convection is the transfer of heat through the vertical movement of air, forming currents in the atmosphere.
🔴 Question 19: Mention two factors affecting the distribution of temperature on Earth.
🟢 Answer: Latitude and altitude are two major factors affecting the spatial distribution of temperature on Earth’s surface.
🟢 Question 20: What is the solar constant?
🟢 Answer: The solar constant is the amount of solar energy received per unit area at the top of Earth’s atmosphere (~1.94 cal/cm²/min).
🌍 Section C — Medium Answer Questions (≈60 words each)
🔵 Question 21: Explain the factors that influence the amount of insolation received on Earth.
🟢 Answer: Insolation varies due to several factors:
Solar angle: Higher at the equator, lower at poles.
Length of day: Longer days mean more insolation.
Earth’s distance from the Sun: Slightly affects intensity.
Atmospheric transparency: Clouds, dust, and gases reduce insolation.
Surface albedo: Reflective surfaces reduce absorption.
These factors control global temperature distribution.
🟡 Question 22: Describe the process of terrestrial radiation.
🟢 Answer: Earth absorbs shortwave solar radiation and re-emits it as longwave infrared radiation known as terrestrial radiation. This energy is partly absorbed by greenhouse gases like water vapour and carbon dioxide, warming the atmosphere. Some is radiated back to space, maintaining Earth’s heat balance. This process regulates surface temperature and drives atmospheric circulation.
🔴 Question 23: Explain the three modes of heat transfer in the atmosphere.
🟢 Answer:
Conduction: Heat transfer through direct molecular contact, warming air near the Earth’s surface.
Convection: Vertical movement of warm air upward and cold air downward, forming convection currents.
Radiation: Transfer of energy through electromagnetic waves without a medium.
Together, these processes distribute heat in the atmosphere, influencing weather and temperature patterns.
🟢 Question 24: Describe Earth’s heat budget and its significance.
🟢 Answer: Earth’s heat budget is the balance between incoming solar radiation and outgoing terrestrial radiation. About 51% of solar energy is absorbed by Earth, 19% by the atmosphere, and 30% is reflected. Earth radiates an equal amount back to space, maintaining temperature equilibrium. This balance regulates climate, supports life, and controls global energy distribution.
🔵 Question 25: What is temperature inversion? Explain its causes.
🟢 Answer: Temperature inversion occurs when temperature increases with altitude instead of decreasing. Causes include:
Radiation cooling of the ground at night.
Cold air drainage into valleys.
Subsidence from high-pressure systems.
Advection of warm air over cold surfaces.
It traps pollutants and affects weather, often leading to fog formation and poor air quality in valleys and basins.
🟡 Question 26: Describe the horizontal distribution of temperature.
🟢 Answer: Horizontal temperature distribution varies due to latitude, land-water contrast, ocean currents, and altitude. Isotherms (lines of equal temperature) shift seasonally. Temperatures are highest near the equator and decrease toward the poles. Land areas heat and cool faster than oceans, creating continental and maritime temperature patterns. Ocean currents also modify temperature distribution globally.
🏞️ Section D — Detailed Answer Questions (≈150 words each)
🔴 Question 27: Discuss the factors affecting the distribution of temperature on Earth.
🟢 Answer: Temperature distribution is influenced by several key factors:
Latitude: Solar angle decreases with latitude, reducing temperature toward the poles.
Altitude: Temperature drops with height due to decreasing pressure and density.
Distance from the sea: Coastal areas have moderate climates, while interiors show extremes.
Ocean currents: Warm currents raise, and cold currents lower temperatures.
Cloud cover: Clouds reduce daytime heating and nighttime cooling.
Slope and aspect: South-facing slopes in the Northern Hemisphere receive more sunlight.
Winds and air masses: Redistribute heat globally.
These factors interact to create varied temperature patterns across regions. Understanding them is crucial for studying climate zones, vegetation distribution, and agricultural patterns. The interplay of these elements shapes Earth’s climatic diversity and influences weather systems worldwide.
🟢 Question 28: Explain the process of solar radiation and its interaction with the atmosphere.
🟢 Answer: Solar radiation is electromagnetic energy emitted by the Sun. As it reaches Earth, about 30% is reflected by clouds, atmosphere, and surface (albedo), 19% is absorbed by the atmosphere, and 51% is absorbed by Earth’s surface. The absorbed energy heats the land and water, which reradiate it as terrestrial radiation. Greenhouse gases absorb part of this energy, warming the lower atmosphere. Scattering, reflection, and absorption modify solar radiation during its journey. This interaction regulates temperature, drives atmospheric circulation, and influences weather and climate. The balance between incoming and outgoing radiation ensures a stable climate system. Disruptions, such as increased greenhouse gases, can enhance the greenhouse effect, leading to global warming.
🔵 Question 29: Discuss the vertical distribution of temperature in the atmosphere.
🟢 Answer: Temperature generally decreases with altitude in the troposphere (~6.5 °C/km) due to decreasing pressure and density. In the stratosphere, temperature increases with height because ozone absorbs ultraviolet radiation. The mesosphere experiences a sharp temperature decline, reaching -90 °C. In the thermosphere, temperature rises due to solar radiation absorption. Factors like lapse rate, temperature inversion, and adiabatic processes influence vertical temperature variation. These patterns affect cloud formation, weather phenomena, and aircraft operations. Understanding vertical temperature distribution is essential for meteorology, aviation, and climate studies as it determines atmospheric stability, convection patterns, and heat transfer dynamics.
🟡 Question 30: Explain the significance of Earth’s heat balance in maintaining climate and life.
🟢 Answer: Earth’s heat balance ensures that incoming solar radiation equals outgoing terrestrial radiation, maintaining a stable average temperature (~15 °C). This balance regulates global climate, supports the hydrological cycle, and sustains life. It controls atmospheric circulation, redistributes heat between equator and poles, and influences wind and ocean current systems. Without balance, Earth would experience extreme temperatures, making life impossible. Human activities disrupting this balance, such as greenhouse gas emissions, cause global warming and climate change. Understanding heat balance is essential for predicting weather, studying climate systems, and managing environmental challenges. It highlights the interconnectedness of solar energy, atmospheric dynamics, and life on Earth.
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