What is it?• Climate change is a significant and lasting change in the statistical distribution of weather patterns over periods ranging from decades to millions of years. It may be a change in average weather conditions, or in the distribution of weather around the average conditions. Climate change is caused by factors that include oceanic processes, variations in solar radiation received by Earth, plate tectonics and volcanic eruptions, and human-induced alterations of the natural world; these latter effects are currently causing global warming, and "climate change”.
Causes• The global increase in demand and energy consumption and industrial activity, transport, agriculture and deforestation, have led to an increase in emissions of CO2 and methane, the main greenhouse gas causing climate change.
Effects• According to the IPCC (International Panel of Experts on Climate Change), the global warming of the Earth is already a fact that is occurring, and will produce serious consequences on the climate, atmosphere and biodiversity: increasing the average temperature of the Earth in this century between 1 and 3.5 degrees, reduced ice caps at the poles, sea level rise and flooding of low lying areas and islands, increasing desertification, disappearance of flora and fauna in ecosystems, shortages water and atmospheric instabilities (hurricanes, fires, etc..), side effects of human catastrophes (spread of famine and disease, etc..).
Solutions• Climate change is a global problem requiring a global solution. Measures to alleviate this terrible future abide pass guidelines agreements like the Kyoto Protocol: reduce CO2 emissions, reduce the use of fossil fuels and renewables increase, improve efficiency and energy diversification, pursue a policy of sustainable development and especially aware of the seriousness of the problem to future generations.
What is global warming?• Global warming is the rise in the average temperature of Earths atmosphere and oceans since the late 19th century and its projected continuation. Since the early 20th century, Earths mean surface temperature has increased by about 0.8 °C (1.4 °F), with about two-thirds of the increase occurring since 1980. Warming of the climate system is unequivocal, and scientists are more than 90% certain that it is primarily caused by increasing concentrations of greenhouse gases produced by human activities such as the burning of fossil fuels and deforestation.
What is greenhouse effect?• The greenhouse effect is a process by which thermal radiation from a planetary surface is absorbed by atmospheric greenhouse gases, and is re- radiated in all directions. Since part of this re-radiation is back towards the surface and the lower atmosphere, it results in an elevation of the average surface temperature above what it would be in the absence of the gases.Solar radiation at the frequencies of visible light largely passes through the atmosphere to warm the planetary surface, which then emits this energy at the lower frequencies of infrared thermal radiation. Infrared radiation is absorbed by greenhouse gases, which in turn re-radiate much of the energy to the surface and lower atmosphere. The mechanism is named after the effect of solar radiation passing through glass and warming a greenhouse, but the way it retains heat is fundamentally different as a greenhouse works by reducing airflow, isolating the warm air inside the structure so that heat is not lost by convection.
Climate change in America• Latin America is especially vulnerable to climate change because of its geography. First, most of Mexico and Central America is within the hurricane belt, which now acts more strongly and volatility as a result of global warming. Second, the low coastal areas of Latin America - including its many islands and several urban areas in the region - will be threatened by rising sea levels induced by global warming. Third, much of the urban and agricultural activities in South America depends on water that comes from the Andean glaciers, which are also affected by being dangerously warming. All this threatens the sustainability of the regions populations and economies and, in particular, the main source of low-carbon energy in the region - hydropower.
Climate change in Asia• Asia is undoubtedly one of the regions most vulnerable to the consequences of climate change. In 2007, 75% of people who died as a result of a natural disaster and lived in this area for the past three years the number of natural emergencies in that continent grew from 50 to 200 per year.
Climate change in Europe• The average temperature in Europe has increased in the last 100 years 0.95 degrees Celsius, which means a 35% higher than the average warming of the planet (0.7 degrees). The greatest warming has been recorded in the Iberian Peninsula, northwest Russia and some Arctic regions. The 75% of alpine glaciers, if the trend continues, it will have thawed in 2050.
Climate change in Africa• Increasing deforestation in Africa has much of the blame for the frequent droughts and floods in the east of the continent each year suffering the effects of climate change and the threat that hangs over the plant and animal species in danger of extinction are in the area. The area of glaciers in the Africa has decreased by nearly 550 acres in one hundred years.
Climate change in Oceania• Climate change has become a major issue in Australia due to drastic climate events since the turn of the 21st century that have focused government and public attention. Rainfall in Australia has increased slightly over the past century, although there is little or no trend in rainfall in northeast and southwest Australia. Water sources in the South Eastern areas of Australia have depleted due to increasing population in urban areas (rising demand) coupled with climate change factors such as persistent prolonged drought (diminishing supply). At the same time, Australia continues to have the highest per capita greenhouse gas emissions.The federal government and all state governments (New South Wales, Victoria, Queensland, South Australia, Western Australia, Tasmania, Northern Territories and Australian Capital Territory) have explicitly recognised that climate change is being caused by greenhouse gas emissions, in conformity with the scientific opinion on climate change. Sectors of the population are actively campaigning against new coal mines and coal fired power stations because of their concern about the effects of global warming on Australia. There is expected to be a net benefit to Australia of stabilising greenhouse gases in the atmosphere at 450ppm CO2 eq.
Here are some photos of Climate Change Then and Now
Thanks for watching the video.• By Federico Penic