Air Pollution and Global Change 181
a substantial part of the energy deficit that would be caused by the reduction of fossil fuels. In the array of various renewable energy sources, wind
energy is a mature technology and is the most promising solution, followed
by exploitation of solar energy, utilization of biomass and agricultural
waste, and wave and tidal energy. Hydroelectric energy is also a renewable source but it may have potentially high environmental impacts. Solar
energy production is growing rapidly in some countries due to the increase
of the use of photovoltaic systems and other technologies. Key concerns are
how much it will cost to “stabilise” the climate and minimize manmade
climate change and to what extent the cost of avoiding dangerous climate
change will compete with other priorities such as development.
9.4.2 Earth’s Climate
The alterations brought about by human activities on the environment during the industrial era, the principal one being air pollution but also land
use changes, are now manifested on such scale that they influence the general state of the planet. They are considered on the whole to be an interrelated system of disturbances usually called global change; the intensifying
greenhouse effect and the attendant anthropogenic climate change (which,
according to many indications, has already begun), as well as desertification and perturbation of the hydrological cycle, are the most important.
The climate is the total of the average values of various elements that
define the weather, such as temperature, humidity, rains, winds, snow as
well as violent meteorological phenomena like storms, typhoons etc. All
of these are manifestations of the movements and changes of the troposphere that interact with the various physicochemical processes, the action
of live organisms and extraordinary events like volcanic explosions. The
driving force of all this is solar energy that gets trapped in the atmosphere.
Consequently, the amplification of the greenhouse effect, which means
more energy in the atmosphere, entails not only a rise in temperature but
also a wider perturbation of the planet’s climate.
The climate of the Earth does not present great changes mainly because
of the longstanding stability of the atmosphere. A different composition
of the atmosphere would probably mean a very different average climate.
Of course, the climate presents great differences according to the geographic
latitude and local geomorphological conditions but it also undergoes small
changes in relation to time. Thus the climates of various regions have undergone observable changes throughout history. Man has always been adapting
to the climate of his region, and sometimes he has succeeded in changing it
on a local level.
Various paleontological findings and other scientific data inform us about
Earth’s climate in the last million years of its geological history. There is a
continuous cyclic alternation between a warmer and a colder climate, with
a substantial part of the energy deficit that would be caused by the reduction of fossil fuels. In the array of various renewable energy sources, wind
energy is a mature technology and is the most promising solution, followed
by exploitation of solar energy, utilization of biomass and agricultural
waste, and wave and tidal energy. Hydroelectric energy is also a renewable source but it may have potentially high environmental impacts. Solar
energy production is growing rapidly in some countries due to the increase
of the use of photovoltaic systems and other technologies. Key concerns are
how much it will cost to “stabilise” the climate and minimize manmade
climate change and to what extent the cost of avoiding dangerous climate
change will compete with other priorities such as development.
9.4.2 Earth’s Climate
The alterations brought about by human activities on the environment during the industrial era, the principal one being air pollution but also land
use changes, are now manifested on such scale that they influence the general state of the planet. They are considered on the whole to be an interrelated system of disturbances usually called global change; the intensifying
greenhouse effect and the attendant anthropogenic climate change (which,
according to many indications, has already begun), as well as desertification and perturbation of the hydrological cycle, are the most important.
The climate is the total of the average values of various elements that
define the weather, such as temperature, humidity, rains, winds, snow as
well as violent meteorological phenomena like storms, typhoons etc. All
of these are manifestations of the movements and changes of the troposphere that interact with the various physicochemical processes, the action
of live organisms and extraordinary events like volcanic explosions. The
driving force of all this is solar energy that gets trapped in the atmosphere.
Consequently, the amplification of the greenhouse effect, which means
more energy in the atmosphere, entails not only a rise in temperature but
also a wider perturbation of the planet’s climate.
The climate of the Earth does not present great changes mainly because
of the longstanding stability of the atmosphere. A different composition
of the atmosphere would probably mean a very different average climate.
Of course, the climate presents great differences according to the geographic
latitude and local geomorphological conditions but it also undergoes small
changes in relation to time. Thus the climates of various regions have undergone observable changes throughout history. Man has always been adapting
to the climate of his region, and sometimes he has succeeded in changing it
on a local level.
Various paleontological findings and other scientific data inform us about
Earth’s climate in the last million years of its geological history. There is a
continuous cyclic alternation between a warmer and a colder climate, with