Why and to what extend is the carbon dioxide content changing in the atmosphere? Is this change enhancing the greenhouse effect?
Is the threat of global warming myth or fact? Many observers look alarmingly to the 1980’s – a decade of unprecedented warmth – to confirm their fears that global warming is real. Yet a short-term trend such as this can mean very little. What about global temperatures over the long term? As it turns out, long-term studies verify that global temperatures have indeed been increasing, although sporadically, since the turn of the century.
What is causing global temperatures to rise? Many environmental scientists point to the increasing atmospheric concentrations of greenhouse gases – carbon dioxide (CO2), water vapor (H2O), methane (MH4), nitrous oxide (N2O), ozone (O3), and chloroflourocarbons (CFC’s). A clear, historical link has been established between CO2 concentrations and global temperature change. By analyzing tiny bubbles of air trapped in ice core samples, scientists have learned that, in the past, when atmospheric CO2 concentrations increased, so did global temperatures. Periods of markedly low CO2 concentrations corresponds to periods of extreme cold, i.e., the ice ages.
In this lab, you will investigate both short-term and long-term trends in concentrations of CO2 in the atmosphere and identify some of the causes and effects of global warming.
To graph changes in atmospheric CO2 concentration and to interpret the graph.
To correlate trends in CO2 concentrations with future climate change.
anthropogenic: originating in human activity (chiefly of environmental pollution and pollutants).
climate change: Change in the statistical distribution of weather over periods of time that range from decades to millions of years
greenhouse effect: The warming of the atmosphere by the trapping of long-wave radiation being radiated to space. The gases most responsible for this effect are water vapor and carbon dioxide.
fossil fuels: Fossil fuels, coal, oil and natural gas, are a non-renewable source of energy. Formed from plants and animals that lived up to 300 million years ago, fossil fuels are found in deposits beneath the earth. The fuels are burned to release the chemical energy that is stored within this resource. Energy is essential to modern society as we know it. Over 85% of our energy demands are met by the combustion of fossil fuels.
pollution: The release of harmful environmental contaminants, or the substances so released. Generally the process needs to result from human activity to be regarded as pollution. Even relatively benign products of human activity are liable to be regarded as pollution, if they precipitate negative effects later on. The nitrogen oxides produced by industry are often referred to as pollution, for example, although the substances themselves are not harmful.
ppm: Parts Per Million; In science and engineering, the parts-per notation is a set of pseudo units to describe small values of miscellaneous dimensionless quantities, e.g. mole fraction or mass fraction.