meteorology

Topic: Weather & Climate

Definition of Weather and Climate

  • Weather: The state of the atmosphere with respect to heat or cold on a given day.

  • Climate: The average course or condition of the weather in a specific location over a longer period.

Key Differences:

  • Weather can change from day to day, while climate varies significantly from one location to another.

Factors Affecting Weather & Climate

  1. Precipitation:

    • Refers to all forms of moisture that fall to the Earth's surface, including:

      • Rain

      • Sleet

      • Snow

      • Hail.

    • This term encompasses all forms of moisture that can fall as liquid or solid.

  2. Temperature & Pressure:

    • Temperature and pressure are closely related; generally, higher pressure corresponds to cooler air and lower pressure to warmer air.

  3. Humidity:

    • Defined as the amount of water vapor present in the air compared to the maximum amount of water vapor that the air can hold at a given temperature.

    • Expressed as a ratio or a percentage, it indicates the moisture level in the atmosphere.

Types of Clouds:

Clouds are classified into three primary levels, each with its specific types. In total, there are ten fundamental cloud types:

  1. High-Level Clouds (5-13 km):

    • Cirrocumulus

    • Cirrus

    • Cirrostratus

  2. Mid-Level Clouds (2-7 km):

    • Altocumulus

    • Altostratus

    • Nimbostratus

  3. Low-Level Clouds (0-2 km):

    • Stratus

    • Cumulus

    • Cumulonimbus

    • Stratocumulus

Contrails

Cloud Types Contraction Diagram

  1. Cirrocumulus

  2. Cirrostratus

  3. Cirrus

  4. Cumulonimbus

  5. Altostratus

  6. Altocumulus

  7. Cumulus

  8. Nimbostratus

  9. Stratocumulus

  10. Stratus

Global Warming and Ozone Layer

The Greenhouse Effect

  • The greenhouse effect is a natural process that warms the Earth's surface.

  • When solar energy reaches the Earth's atmosphere, it can either be reflected back into space or absorbed and re-radiated by greenhouse gases.

  • These gases function as a blanket around the Earth, absorbing infrared (IR) radiation and preventing it from escaping into space.

Implication: This leads to the gradual warming of Earth's atmosphere and surface, known as global warming.

Industries and Greenhouse Gases

  • Industries involved in manufacturing insulating foams, solvents, soaps, and refrigeration materials utilize substances known as chlorofluorocarbons (CFCs), which are potent greenhouse gases contributing to climate change.

Ozone

  • Ozone (O3) is a naturally occurring gas that is replenished over time in the atmosphere.

  • It plays a critical role in filtering harmful solar radiation.

Steps in Ozone Depletion:

  1. CFCs are released into the environment by industrial processes.

  2. These CFCs rise up to the stratosphere, where they are broken down by sunlight, releasing chlorine atoms.

  3. Chlorine reacts with Ozone (O3) and destroys ozone molecules.

  4. This reaction continues, leading to further depletion of ozone.

Smog

Definition

  • Smog is a type of severe air pollution characterized by a mixture of smoke and fog, often resulting from industrial emissions, vehicle exhaust, and other pollutants.

Formation of Smog:

  • In colder months, cooler temperatures and dry winds create a high-pressure system, resulting in a cool layer in the atmosphere.

  • The warm air above this cool layer acts as a lid, trapping smog close to the ground.

  • Pollutants such as nitrogen oxides (NO), volatile organic compounds (VOCs), and particulate matter (PM) react with sunlight to produce various photochemical toxins, further exacerbating air quality issues.