Global warming is leading to climate change.- Juan Arango Millan

Global warming is a long-term increase in the average temperature of the Earth's near-surface air and oceans, which began in the late 19th century. Global warming is projected to continue throughout the 21st century, with increasing rates that depend on future emissions of greenhouse gases. The consensus within the scientific community is that it is caused primarily by human activities such as carbon dioxide emissions from fossil fuel combustion and deforestation. The term global warming has been used to refer to the modern temperature increase and its effects, as well as more generally to climate change in general. The first usage of this term was in a 1975 paper by Wally Broecker in the journal Science. Global warming and climate change are often used to refer to a variety of effects of increased global temperatures. The most common usage is to describe the observed century-scale rise in the average temperature of Earth's near-surface air and oceans since the late 19th century, and its projected continuation. The term "global warming" is also used to refer to long-term temperature increases in the lower atmosphere that may be attributed to greenhouse gas emissions. In the modern era, Earth's average surface temperature has increased by about 0.8 °C (1.4 °F) over the last century, with about two-thirds of this increase occurring since 1980. This has been the result of an increase in greenhouse gas concentrations, resulting primarily from fossil fuel emissions and deforestation. The Intergovernmental Panel on Climate Change (IPCC) concludes that "most of the observed increase in globally averaged temperatures since the mid-20th century is very likely due to the observed increase in anthropogenic greenhouse gas concentrations." The global warming controversy refers to a variety of disputes over the nature, causes, and consequences of global warming. The most publicized concerns an ongoing debate over whether or not human activity is causing global warming, how much warming has occurred in recent decades, what impacts it will have in the future and how best to respond. Global warming has become an important political and economic topic, with some arguing it is a crisis that must be addressed through legislation. Others say that the effects of global warming are still too uncertain to justify economically disruptive measures like cap and trade or carbon taxes. Since the late 1990s, public concern over global warming has increased. Various factors, including media coverage of climate-related issues and an extensive science communication campaign by environmental groups, have driven this. The economic costs of climate change mitigation policies are controversial. Proponents of the scientific consensus view say that the economic costs of mitigation policies have been exaggerated by some industries and interest groups, while others dispute this. A 2010 survey of 1,372 climate scientists published in the journal "Nature" found that a majority (70%) felt that temperatures would rise more than 2 degrees Celsius above pre-industrial levels within 50 years without policy action to reduce emissions. Studies on the economic effects of mitigation policies have produced diverse results. Some studies show that mitigation policies are likely to have net benefits for the economy, while others suggest that they will cause significant harm. The discrepancy in findings is due in part to different assumptions about how policy interventions will affect greenhouse gas emissions and GDP growth rates. A study published in the "Journal of Economic Perspectives" found that significant uncertainty exists regarding the economic effects of mitigation policies, but also concluded that there is no compelling evidence that these policies would cause substantial harm. The same study noted that many economists believe that greenhouse gas emissions can be reduced at low cost or even without negative effects on GDP growth rates if governments adopt appropriate policies. A study published in the "Journal of Economic Perspectives" found that significant uncertainty exists regarding the economic effects of mitigation policies, but also concluded that there is no compelling evidence that these policies would cause substantial harm. The same study noted that many economists believe that greenhouse gas emissions can be reduced at low cost or even without negative effects on GDP growth rates if governments adopt appropriate policies.