Earth has experienced at least five Ice Ages: the Huronian, the Cryogenian, the Andean-Saharan, the Karoo, and the Quaternary. The latest of these is the Quaternary Ice Age, which began 2.6 million years ago and is still ongoing. That might sound off given that the popular conception of an ice age is of a world blanketed in snow and roaming with wooly mammoths, but the scientific definition only requires that a substantial ice sheet be present on the Earth’s surface, and Antarctica fits the bill. While their causes vary, ice ages are typified by periods of sustained global cooling and glacial expansion. Going by this, the Little Ice Age qualifies, though it is also an ice age within an ice age, making it a sort of matryoshka doll climate event. The Little Ice Age is not the only lesser ice age, though it is the best known as it occurred the most recently and within recorded history. After having touched on similarities, our next logical step is to examine what makes the Little Ice Age different.
Acid Deposition (commonly known as Acid Rain) means precipitation that has acidic components, i.e. an unusually low pH level (4.2~4.4). Acid rain is a term coined in 1852 by Robert Angus Smith, a Scottish scientist who conducted rainwater experiments in industrial regions throughout Scotland and England.
Petroleum (or oil) and natural gas are widely used sources of fuel. Around the world many transportation, energy, and heating infrastructures depend in large part on one or both of these hydrocarbon-rich fuels, petrochemical products. While in the past it may have seemed inconceivable that people would have to step away from fossil fuels, climate change increasingly necessitates greener alternatives. It is also hard to imagine life without plastics. For many applications, such as in healthcare, there may be no better materials. A future with zero plastic is neither warranted nor desirable, but the threats to various ecosystems are likely to force the development of greener and more sustainable materials.
Are carbon emissions (carbon dioxide) good or bad for our environment? In this lesson, we will explore why carbon emissions are good and why carbon emissions are bad.