Causes of Climate Change - Climate Resilient Agriculture for Ensuring Food Security - page 20

Fig. 2.1 Graphical representation of the greenhouse effect (Source: CO 2 Cooperative Research Centre)

￿ The amount of radiation that the gas absorbs
and the wavelength at which it absorbs
￿ The time that the gas stays in the atmosphere
before reacting or being dissolved in rainwater
or the ocean
￿ The current concentration of the gas in the
atmosphere
￿ Any indirect effects of the gas (e.g., meth-
ane will produce ozone gas in the lower atmo-
sphere and water vapor in the stratosphere)
The GWP of methane is 25 times as potent a
greenhouse gas as carbon dioxide, and nitrous
oxide is 298 times as potent a greenhouse gas as
carbon dioxide.

Fig. 2.2 Contribution of different sectors in the world to
climate change (Sources of greenhouse gas emissions)

The contribution of each of the greenhouse
gases to global warming is dependent on its
global warming potential (GWP), expressed as
carbon dioxide equivalent (CO 2 e). The GWP
takes into account:

2.3.1 Water Vapor

Water vapor is the most abundant greenhouse gas,
but importantly, it acts as a feedback to the climate.