Global Warming

Summary

Global warming is the long-term rise in Earth's average surface temperature, primarily from increased anthropogenic greenhouse gases.

Core concept

Understand the system

Global warming is the long-term rise in Earth's average surface temperature, primarily from increased anthropogenic greenhouse gases.

Why / how it happens

Causes and context

Global warming is the long-term rise in Earth's average surface temperature, primarily from increased anthropogenic greenhouse gases. The governing relationship is: Greenhouse gases absorb and re-emit outgoing longwave radiation, changing the energy balance until the climate system warms.

Mechanism / process

Greenhouse gases absorb and re-emit outgoing longwave radiation, changing the energy balance until the climate system warms.

Key facts

• The natural greenhouse effect makes Earth habitable; anthropogenic emissions strengthen it.
• Water vapour is a feedback in current warming, while carbon dioxide is a primary forcing.
• Oceans absorb much of the excess heat in the climate system.

Important terminology

• greenhouse effect
• longwave radiation
• carbon sink
• forcing
• albedo

Named examples / case studies

• Ocean heat uptake moderates atmospheric warming while contributing to thermal expansion and sea-level rise.

Causes / components

• Key components: greenhouse effect, longwave radiation, carbon sink.
• Greenhouse gases absorb and re-emit outgoing longwave radiation, changing the energy balance until the climate system warms.

Effects / significance

• Water vapour is a feedback in current warming, while carbon dioxide is a primary forcing.
• Oceans absorb much of the excess heat in the climate system.
• Application: Ocean heat uptake moderates atmospheric warming while contributing to thermal expansion and sea-level rise.

Geography connection

Ocean heat uptake moderates atmospheric warming while contributing to thermal expansion and sea-level rise. This illustrates how global warming varies by location, scale or environmental context.

Bangladesh connection

Warming compounds Bangladesh's heat stress, evapotranspiration, crop risks, sea-level and coastal salinity pressures.

BCS preliminary facts

• The natural greenhouse effect makes Earth habitable; anthropogenic emissions strengthen it.
• Water vapour is a feedback in current warming, while carbon dioxide is a primary forcing.
• Oceans absorb much of the excess heat in the climate system.

BCS written analysis

Build an analytical answer

• Global warming is the long-term rise in Earth's average surface temperature, primarily from increased anthropogenic greenhouse gases.
• Greenhouse gases absorb and re-emit outgoing longwave radiation, changing the energy balance until the climate system warms. Use ocean heat uptake moderates atmospheric warming while contributing to thermal expansion and sea-level rise. as a named application in a comparative answer.

Common misconceptions

• Global warming and climate change are related but not exact synonyms.
• The natural greenhouse effect is not itself a harmful human invention.

Quick revision

• Global Warming
• The natural greenhouse effect makes Earth habitable; anthropogenic emissions strengthen it.
• Water vapour is a feedback in current warming, while carbon dioxide is a primary forcing.
• greenhouse effect / longwave radiation
• Definition → process → spatial example