Global warming occurs as a consequence of natural events. There are impacts by nature, and as daunting as it may seem to attempt to mitigate such large scale events it is possible. Volcanoes and forest fires add greenhouse gases that trap the energy of the sun. In the case of forest fires, one might be more vigilant so as to not cause one, but still. lightning will start a large number of fires each year. A forest fire is particularly problematic since trees remove carbon dioxide from the air, and return oxygen. Carbon dioxide is a known greenhouse gas, the one most easily controlled. In addition to removing the trees that reduce the carbon dioxide from the air, burning trees and brush combines the carbon organic materials stored in the trees and brush with oxygen to form carbon dioxide, adding to the amount of greenhouse gases of the atmosphere.
The best defense is reforestation. But, that should not deter an individual from getting involved. Replacing the lost trees does not need to happen in the same place as the original forest, nor as an entire forest all in a single place. Plant a tree, or better, plant a few trees. This would be your part in offsetting nature. A tree planted properly will flourish better than a seedling growing in a crowded forest, so your trees can make a significant difference.
What if you have no place to plant a tree? Well, join an Earth Day event of planting. Organizers of such an event will have space and seedlings for planting, but often need help in getting them into the ground, or money to offset the expenses. Support such movements, even if you are physically unable to do the actual work yourself. Or, find a service that plants trees on a preserve and sponsor a few trees. Trees are usually of nominal cost to sponsor, and you will know you are alleviating some of the damage done by nature.
With natural events mitigation by offsetting is our best way to respond.