Earth’s Climate Earth is a special planet in the solar systemMercury has no atmosphereIts temperature is usually around 450°C to -170 °CVenus is 100 times denser than earth with a temperature of about 700 °CMars has an atmosphere 100 times less dense than earth with average temperature of -70 °C

ONLY EARTH CAN SUPPORT LIFEIt is because of earth’s climate system

Earth’s climate system keeps earth’s temperature relatively constant and thus habitable.

Components of earth’s climate system 1. Atmosphere

2. Hydrosphere

3. Lithosphere

4. Biosphere

Layers of the Earth's atmosphere

Atmosphere

Nitrogen 78%, Oxygen 21% , hydrogen, argon CO2,etc

Ozone in the atmosphereThe Ozone Layer: The stratosphere contains a thin layer of ozone which absorbs most of the harmful ultraviolet radiation from the Sun. The ozone layer is being depleted, and is getting thinner over Europe, Asia, North American and Antarctica --- "holes" are appearing in the ozone layer.

Do you know why there are "ozone holes"?Scientists have seen ozone holes over antartica since 1970. Ozone is destroyed by the CFCs , the gases used in refrigeration etc.

HydrosphereThe hydrosphere is the "water sphere" that includes all the water of the earth system. Water of the hydrosphere is constantly cycling between the various components of the hydrologic cycle .

Water vapours in clouds reflect some of the energy from sun.

The water Cycle

Climate Zones and waterWater absorbs & stores more thermal energy than land It heats up and cools down more slowly than landRegions near the water such as british Columbia have moderate weather both in summer and in winter.They may also have more rain than land farther away.

2% of earth’s water is frozen Most of it is Arctic and Antarctic

Large sheets of ice reflect sun’s energy which makes these regions very cold.

The lithosphere is the solid, rocky crust covering entire planet. This crust is inorganic and is composed of minerals. It covers the entire surface of the earth from the top of Mount Everest to the bottom of the Mariana TrenchAlong with hydrosphere, it absorbs most of the higher energy radiation from sun and reflects back as lower radiation as infra-red

Lithosphere

Mountains and other landforms affect how air moves over an areaAs clouds move over the mountains they lose their moisture and the other side gets lesser rain. This is called RAIN SHADOW EFFECT

The biosphere is all about life. Physical geographers use the term biosphere to describe our living world. This is where all of the trees, bugs, and animals live. The biosphere extends to the upper areas of the atmosphere where birds and insects can be found. It also reaches deep into the ground at a dark cave or to the bottom of the ocean at hydrothermal vents. The biosphere extends to any place that life (of any kind) can exist on Earth.

The biosphere is the one place where all of the other spheres of the planet work together. Think about the interactions for a second. The land interacts with the water (hydrosphere). The land interacts with the air (atmosphere and climates). The land even interacts with forces deep inside the Earth and the energy coming to the Earth from space. All of those forces work together to create our living world.