Global warming is the process of gradually increasing the temperature of planet Earth.
The main cause is the increasing amounts of greenhouse gases. These gases have a natural origin, but the most significant increase is due to human activity.
The increase in gas emissions increased considerably during the industrial revolution. Industries introduced steam engines that involved burning fossil fuels - especially coal, oil, and natural gas. The industrial revolution caused a sharp increase in CO 2 concentrations .
Important climate variations in history
Historically, various variations in Earth's climate have led to crossing different ice ages alternated with warmer periods. These periods are called interglacial eras.
The variations are mainly due to periodic changes in the orbital design of our planet. These changes are caused by disturbances due to the periodic development of solar activity and volcanic eruptions (due to the emission of carbon dioxide gases and dust).
What are the causes of global warming?
All the main factors to which climate change is attributed are related to people. In particular these are:
- Greenhouse gases. Increased concentration of greenhouse gas levels in the Earth's atmosphere. Gas emission tends to increase.
- Deforestation. Changes in the Earth's surface such as deforestation.
- Increased aerosols. An aerosol is a suspension of fine solid or liquid particles in a gas. In everyday life, the word aerosol generally refers to the suspension that comes out of a spray.
- Intensive breeding.
Recent climatic changes have been analyzed in more detail only since the last 50 years. Because human activities have grown exponentially and observation of the upper troposphere has been possible.
Report of the Intergovernmental Panel on Climate Change
The Intergovernmental Panel on Climate Change (IPCC) made a report on this. The report concludes that most of the observed temperature increases since the mid-20th century are likely due to the increase in man-made greenhouse gases
The same report indicates that it is highly unlikely (estimated to be below 5%) that climatic increases can be explained using only natural causes. Warming affects both the ocean and the atmosphere.
What are the consequences of global warming?
Among the most important consequences we highlight:
- Warmer temperatures. These temperatures mean that climates change: this causes droughts and, in addition, increases the risk of fires that lead to deforestation and desertification of the planet.
- More intense storms. The rains are less frequent, but they are more intense.
- Disease spread. A higher temperature can cause it to become more welcoming to the spread of certain diseases.
- Stronger heat waves. Heat waves can endanger the health and even the lives of thousands of people.
- The melting of glaciers. This means that the sea level rises.
- Most dangerous hurricanes. The rising temperature of the sea makes hurricanes more violent.
- Change in ecosystems caused by changes in the duration of the seasons.
Rising temperatures are causing significant ice losses and rising sea levels. The consequences on the structures and intensity of precipitation are also visible, with consequent changes in the position and size of subtropical deserts.
What situation are we currently in?
By global warming we mean an increase in average temperatures on Earth's surface. This increase began to be observed at the beginning of the 20th century.
Most of the temperature increases have been observed since the mid-20th century. These variations increase with an uneven distribution of global warming across the world. It has a maximum peak in the northern hemisphere from mid to high latitudes to the north pole.
The sharpest point is found more frequently on land than in the seas and oceans (for example, Siberian and Canadian territory) and a lower level in the southern hemisphere, surrounded by oceans. The south pole area encounters a warming trend.
Increased gas emission.
This global average increase would be attributable to the emission of gases. Increased atmospheric concentration of greenhouse gases, in particular carbon dioxide. High levels of gases indicate that it is a consequence of human activity. In particular, the generation of energy by fossil fuels (natural gas, coal, oil) and deforestation, which at the same time generates an increase in the greenhouse effect.
The global darkening, caused by the increased concentration in the atmosphere of aerosols, which blocks the rays of the sun.
What is sustainable development?
Sustainable development is development that meets the needs of the present without compromising the ability of future generations to meet their own needs.
Sustainability is about the scarcity of resources that generate wealth, both now and in the future. The surface of the earth is finite; raw materials may be depleted; and the absorption capacity of the atmosphere and our natural environment has its limits.
The terms sustainability and sustainable use originate from forestry. Later they were also used in fishery biology. In both cases, the meaning was related to concepts of ecology. It was about managing nature in such a way that natural structures and processes were not affected.
Specifically: More wood cannot be extracted from forests than the ability of forests to regenerate.
Future forecasts of the Intergovernmental Panel on Climate Change (IPCC)
IPCC reports suggest that, during the 21st century, the Earth's average temperature may increase further compared to current values, by 1.1 to 6.4 ° C more, depending on the climate model used and the emissions scenario.
Historical thermal series data, held by scientists, indicates that warming is not uniform across the world. It is perceived more accentuated in the northern hemisphere than in the southern one due to:
- The largest distribution of land.
- Relative anthropization
It is also perceived more accentuated on the continent than in the oceans. Greater in northern latitudes than in medium and low latitudes (the Arctic area, Siberia and Canada in strong warming, on the contrary, the Antarctic zone in cooling).
What do the forecasts say about global warming?
Most forecasting models predict that warming will be greatest in the Arctic area. It will lead to a reduction in glaciers, permafrost and frozen seas, with possible changes in the biological network and agriculture.
Global warming and rising temperatures will have different effects from region to region. Its local influences are very difficult to predict.
As a result of increased carbon dioxide in the atmosphere, the oceans could become more acidic.
Measures to avoid global warming
Some measures to reduce global warming are:
Climate mitigation is defined as a human intervention to reduce the release of greenhouse gases from sources and improve the operation of so-called wells.
Well is understood as any process, activity or mechanism that removes greenhouse gases, aerosols or what precedes it from the atmosphere.
Adaptation is defined as "the process of adaptation to current or expected climate change".
In human systems, this means that the damage is limited and that benefits can be obtained. In natural systems, people can facilitate change.
A related term is adaptive capacity: the ability of systems, organizations, people, and other organisms to adapt to global warming.
Geoengineering or climate engineering
Geoengineering is the deliberate large-scale adaptation of climate. Two categories can be distinguished:
- Solar radiation management
- CO 2 removal from air.
Do the other planets suffer from global warming?
It has recently been suggested that some of the planets and satellites in the solar system will experience an increase in temperature.
Situation on Mars
On Mars, the supposed rise in temperature stems from an article studying the relationship between sandstorms and surface albedo.
The article is based on only two points, in 1977 and 1997. An analysis of all available data shows an erratic trend in temperature, with no tendency to heat up.
In 2001 the global temperature of Mars was lower than in 1977.
Situation on Jupiter
Some models predict an increase in the temperature of the planet Jupiter by approximately ten degrees in the equatorial areas, after an increase in meteorological activity, but not an increase in the average temperature.
Furthermore, it is a forecast, not directly observed.
Situation on the other planets of the solar system
On more distant planets like Uranus, Neptune shows temperature increases, but it is likely to be a seasonal variation.
We know next to nothing about the meteorology of these planets, which have been observed for a limited time.
The hypothesis that these variations are due to variations in solar activity is in contrast to the very weak variations measured for solar irradiation.
Scientific study of global warming
The scientific study of current global warming carried out by the scientific community (IPCC climatologists) is carried out through two different procedures:
- On the one hand, we analyze the significant measurable scientific data for the so-called detection or reference parameters of the causes mentioned above (air temperature). , ocean temperature (SST), solar activity, greenhouse gas concentrations) to verify the long-term trend of warming or not (analysis of historical series)
- on the other hand, simulation climate models are used that take into account more or less of all the factors involved in the regulation of the climate system that is constructed from knowledge of the state of the art of climate operation taking into account the physical laws (for example irradiation) and feedback processes.
The models, once built, are validated on the basis of past climate data by applying the model to past times and verifying the goodness or otherwise of the simulated climate with the real past.
These simulations allow us to highlight the causes of climate change and operate future forecasts.
Future projections are often called "scenarios" as they take into account various possible levels of carbon dioxide concentration depending on the sustainable development and economic development of different countries on Earth.
These models have often been criticized by so-called skeptics / deniers of climate change, as they could not faithfully reproduce the climate system in all of its physical processes, including feedback.
Models in the 2000s, in addition to a progressive increase in global average temperature, also provide an increase in the water cycle with an increase in extreme events or droughts and floods, something that has been partially confirmed since the 2010s .
Doubling the carbon dioxide concentration
A major problem in climate research related to global warming is the so-called "doubling problem" of the concentration of carbon dioxide in the atmosphere, first studied by Syukuro Manabe with his own GFDL climate model.
This problem is also known as the climate sensitivity problem, or the response of the climate system to carbon dioxide doubling that the models do not calculate a priori, but for which a value of a multiplier parameter must be entered.
This value is not precisely known, but there are more or less accurate estimates. Another source of uncertainty is the so-called parameterization.
The term global warming refers to the increase in temperature that the Earth is undergoing.
The main causes that cause it are:
- The increase in the emission of greenhouse gases.
- Increased aerosols.
- Intensive breeding.
The main consequences are:
- Warmer temperatures.
- More intense storms.
- Disease spread.
- Stronger heat waves.
- The melting of glaciers.
- Most dangerous hurricanes.
- Ecosystem change.
- Fect mitigation.
- Adaptation to the new environment.
- Climatic engineering.