Environmental Issues

As global temperatures increase more water vapor evaporates, the water in the troposphere increases and more water condenses to form clouds.
Global warming is caused by the activities of the human race and has become very severe with the situation worsening by day (Markham, 2009). Approximately 100% of temperature increases in the past fifty years has resulted from the raise in atmosphere of the greenhouse gas concentrations such as water vapor, ozone, carbon dioxide and methane. When sunlight reaches the surface of earth, some of it is absorbed to warm the earth while most is radiated back toward the air (atmosphere) at longer wavelengths than the sunlight. Some of the longer wavelengths get absorbed by the greenhouse gases before they escape to space. Absorption of these longer waves radiant energy causes warming in the atmosphere. Greenhouse gases operate like a mirror reflecting back to earth some heat energy which could have been lost to the space. It causes an increase in global temperatures (Timeforchange, 2009).

The world’s atmosphere contains 0.0001 percent only earth’s water. Nevertheless, it is an important component of global hydrologic cycle. Air currents carry water vapor over land resulting to precipitation which sustains life on earth. One intuitive result of warmer ocean surface is larger water vapor pressure difference between the sea surface and the adjacent atmosphere. This increases rate of evaporation and consequently the rest of the hydrologic cycle rates also increase. Models have suggested that since global warming is increasing the precipitation rate, the increase is likely to result to heavier rainfall instead of frequent rainfalls or rainfalls of long phases (Water encyclopedia, 2009)

These changes in the rain patterns and events can be either beneficial or harmful. This is because increase in the rainfall rates can cause flooding and increased cloudiness cause heating of globe. On the other hand, it could have beneficial effects on agriculture and other water uses. This is therefore both a positive as well as a negative feedback.
Effects of sulfate aerosols on the surface air

There are two major ways in which an increase in sulfate aerosols might lower surface air temperature. First, as suggested by the Environmental News Network, (2009) sulfur dioxide is changed to sulfate aerosols once emitted into the atmosphere. The capability of sulfate aerosols to reflect radiation of the sun is one reason as to why greenhouse gases have not warmed the globe as would be expected. Secondly, aerosols are an essential source of nucleus about which cloud droplets condense.  In the tropical areas, they are a chief source of the condensation. In essence, more the cloud condensation nuclei cause brighter cloud and therefore, additional solar radiation is reflected into space prior to reaching the surface of Earth (Timeforchange, 2009).

The likelihood of ice ages
Ice is likelier when the earth’s tilt is at maximum. This is because if the earth’s tilt is bigger in NH winter, northern latitudes will be farther from the sun compared to where they would be when the tilt is smaller. Hence the entire NH would have a cooler winter (Timeforchange, 2009).
Effect of carbon dioxide on the atmosphere

As the earth warms, it is expected that less CO2 will be dissolved in the oceans. This will result in increased warming because it is anticipated that CO2 has an atmospheric lifespan of fifty to two hundred years. This means that it stays in the atmosphere for a very long period and because the absorption rate is decreasing in the oceans, the warming will become even higher in the nearer future, causing a negative feedback (Markham, 2009).