The concentrations of the greenhouse gases like water vapor, methane, nitrous oxide, ozone, and carbon dioxide are increasing into the atmosphere due to human activities like burning of the fossil fuels, deforestation and due to natural hazards like forest fires and volcanic eruptions.
These gases are capable of absorbing the heat energy from sunlight as a result of this the temperature of the global atmosphere is increasing. This can bring a drastic climatic change as this may lead to the exclusion of some of the seasons, drastic dryness and hotness in the atmosphere.
The nerves in the integumentary system (skin) sense the irritation and send the signal to the brain. The brain then sends impulses through the nervous system to scratch the itch.
