The potential effects of global warming listed here are just a handful of those discussed in the Intergovernmental Panel on Climate Change’s (1PCC) 2007 report.
Rising sea levels are the most common concern among climate change experts; thermal expansion of the oceans – a result of water molecules expanding in warmer temperatures, increased precipitation, and the melting of mountain glaciers.
Mountain glaciers have become much smaller during the past century, especially those in low latitude locations like Mount Kenya in Africa and the Andes in South America.
Since the end of the last ice age, sea levels have risen over 200 meters, on average 0.1-0.2 millimeters (mm) each year. In recent years, however, that has accelerated to l-2mm each year. In the 20th century alone, sea levels rose 0.17 meters and predictions for the next century range anywhere from 0.18 to 0.59 meters.
Because all bodies of water have varying shapes and ocean water tends to “swell” differently depending on its starting temperature, the change in sea level is not uniform over the surface of the Earth.
While smaller projections would likely have only relatively modest impacts, higher projections suggest dramatic effects on low-lying coastal communities as shoreline erosion threatens houses and freshwater supplies become contaminated with salty water.
For example, the country of Bangladesh, which has an extensive coastline and lies between 2 major rivers, is frequently cited as having the potential to suffer some of the greatest damage if sea levels were to rise.
A rise in sea level of 1 meter could force nearly 15 per cent of the country’s land under water and displace up to 13 million people. In addition, certain natural ecosystems across the globe – such as wetlands – would also be in jeopardy with a rapid rise in sea level.
Melting Arctic Sea Ice
Today, the Arctic summer sea ice is about half as thick as it was in 1950. Just like an ice cube melting in a glass of water, the melting Arctic sea ice does not contribute to sea-level rise except for the expansion of seawater with increasing heat however, melting Arctic sea eventually lead to global changes in water circulation the water from melted ice the sea surface that is less dense than the underlying water because it is less salty, potential preventing the pattern of deep ocean currents from rising to the surface. Additionally, melting’s) ice speeds up the warming of the Arctic since water absorbs 80 percentage of sunlight, about same amount that the cover of sea ice used to reflect.
While the idea of swimming in a warmer ocean is pleasant to most human beings, increasing ocean temperatures could cause serious ecological damage. In the past, warm sea-surface temperatures have been responsible for major destruction and can cause more damage if global temperatures continue to climb.
Approximately one quarter of the world’s coral reefs have did over the last few decades, many of them affected by coral bleaching – a process directly tied to warming waters, which weakens the coral animals.
Scientists hypothesize that a warming atmosphere will lead to changes in ocean current and in air circulation patterns that will significantly affect weather across the globe. Global warming appears to push many climates to their extremes – expanding deserts and making usually rainy areas much more so.
An increase in global temperature will likely to enhance the ability for severe weather, which could mean stronger and more frequent storms. Warmer temperatures cause more evaporation oil water, which, as part of the water cycle eventually leads to increased precipitation. In fact, the world has seen a 5-10 percentage increase in precipitation over the past century. Many computer models predict that the frequency of heavy rainfall events is also likely to rise with global warming, further increasing the potential for flooding.
While some parts of the world are projected to experience increased precipitation if warming persists, other parts may experience higher levels of drought.
This is because places that are typically dry – such as the centers of continents – will experience even more evaporation as global temperatures climb. However, scientists are still trying to decipher as to whether drought’ is increasing or whether we are merely experiencing a shift in areas of drought. Either way hotter, drier temperatures in the American West – for example – are leading to extended wildfire seasons that threaten both national forests and private property, in addition to the population within these areas.
Warmer winters mean that many deaths related to cold temperatures might be avoided and that the growing season will last longer, a possible upside to global warming. More people around the world die because of wintertime cold than because of summertime heat.
Decreased wintertime deaths could offset some of the potential increase in summertime heat-related deaths, or even lead to more lives saved as a result of the changed temperatures. With respect to longer growing seasons, there is already evidence in Europe that their growing season has been extended since the 1960s, with spring plants now blooming about 6 days earlier and fall colours coming about 5 days later.
With drought affecting some regions and heat intensifying in the tropics, many areas are becoming unsuitable for agriculture.
In tropical areas that are already dry and hot, the ability to harvest food will likely decrease even with small increases in warming. However, warmer temperatures and increased precipitation can also make previously marginal land more suitable for farming.
Therefore, it is likely that – with a changing climate – a global change in the agricultural pattern will occur. Yet, it is unknown as to whether or not the increase in usefulness of marginal lands will counterbalance the increase in drought and desertification.
Human Health Concerns
In addition to potential environmental changes, the human health implications of increased global warming are also very concerning.
Extreme heat waves during the summers of 2003 and 006 led to thousands of deaths in Europe, North America, and India. Unless steps are taken to avoid this, heat waves are likely to increase – as will their intensity – leading to an even greater number of heat-related deaths.
We are also witnessing the spread of various diseases, and this is likely to increase if temperatures continue to rise. Illnesses that were previously limited to tropical areas may be able o spread further as other areas warm. Higher temperatures also lead to an increase in ground level ozone, which can be an irritant to respiratory systems as well as to eyes.
Other Species Health Concerns
Animals and insects are also affected by global warming, most often related to changes in migration patterns, shorter hibernation time, relocation to new areas, and extinction due to lack adaptation.
Many animals accustomed to living in the arctic regions, such as polar bears have begun to be forced further out of their native habitat in search of more accommodating habitat closer to the poles animals that migrate, such as birds and butterflies, e begun arriving sooner and departing later from their normal patterns, and extending their migratory range closer to the poles.
Most scientists agree that the Earth is in fact experiencing increasing temperatures, and y believe that humans are enhancing this overall warming trend. Much of the controversy mounding global warming will continue to center on the necessary level of concern, what warming will have, and what specific actions should be taken.
The likely effects of global will not be limited to one country – or even one continent – and it will continue to be highly charged issue that permeates almost every aspect of human life and that of the ‘ environment.