Carbon and hydrogen are the basis of organic matter on Earth. The most basic hydrocarbon is methane – CH4. Carbon dioxide is usually thought of as inorganic (although some contend that there is no such thing as inorganic carbon chemistry) is carbon bonded with oxygen. Together methane and carbon dioxide are the two most important determinants for global warming.
Both methane and carbon dioxide are relatively inert – in other words they don’t react with other chemicals or compounds and so stay around for a long time. They are both greenhouse gases. They stay in the upper hemisphere and allow sunlight to pass through them but when ultraviolet light tries to leave the atmosphere it encounters the green house gases and a large portion of it is re-directed to earth. This is causing global warming and also increasing the risk of skin cancer.
The causes for global warming are hotly disputed. Most scientists make the industrial revolution the key event in the exponential growth in greenhouse gases. Others also point to ruminant farming that produces lots of methane.
In both cases it is human activity – one for industry and one for agriculture. Humans themselves breathe out carbon dioxide. The connection therefore between humanity’s security on the planet and humanity’s main activities of breathing, industry and agriculture is irrefutable.
Models of climate change show different things. One short term benefit of more carbon dioxide in the atmosphere will be faster plant growth as plants and algae use carbon dioxide in photosynthesis to make energy to grow.
In the longer term, the rising temperature will melt ice caps and glaciers and cause sea levels to rise.
The ways to lower the carbon count are within our power. Trees, plants and flora in general are great sinks for carbon. Another method is to have a paradigm shift in agriculture and industry. Less livestock would reduce methane emissions. And new systems of energy not based on carbon would also have a positive effect.
If no large scale action is taken population numbers will decrease as climatic conditions become more harsh.