Climate refers to the average weather conditions in a place over a period of time. It includes patterns of temperature, precipitation, humidity, wind, and season. According to the United Nations Framework Convention on Climate Change (UNFCCC), climate change is an alteration to normal climate patterns attributed directly or indirectly to human activity that changes the composition of the global atmosphere and which is in addition to natural climate variability observed over comparable time periods. The UNFCCC draws a distinction between climate change caused by human activities impacting the atmospheric composition, and the variability of climate contributed by natural causes. The nonhuman causes consist of ocean variability, orbital variations, solar output, volcanism and plate tectonics, whereas the human influences mainly include carbon dioxide emissions from fossil fuel combustion, land use, ozone depletion, animal agriculture and deforestation. The change of climate patterns fundamentally impacts the natural ecosystems, and the human economies and cultures that depend on them. From an ethical and political stance, climate change gives birth to a series of issues related to justice, (in)equality, human rights, collective rights, and historical responsibility.