Global warming

Climate change is caused by factors such as biotic processes, variations in solar radiation received by Earth, plate tectonics, and volcanic eruptions. Certain human activities have also been identified as significant causes of recent climate change, often referred to as "global warming".

On the broadest scale, the rate at which energy is received from the sun and the rate at which it is lost to space determine the equilibrium temperature and climate of Earth. This energy is distributed around the globe by winds, ocean currents, and other mechanisms to affect the climates of different regions.

Factors that can shape climate are called climate forcings or "forcing mechanisms". These include processes such as variations in solar radiation, variations in the Earth's orbit, mountain-building and continental drift and changes in greenhouse gas concentrations. Some parts of the climate system, such as the oceans and ice caps, respond slowly in reaction to climate forcings, while others respond more quickly.

Forcing mechanisms can be either "internal" or "external". Internal forcing mechanisms are natural processes within the climate system itself (e.g., the thermohaline circulation). External forcing mechanisms can be either natural (e.g., changes in solar output) or anthropogenic (e.g., increased emissions of greenhouse gases).

Whether the initial forcing mechanism is internal or external, the response of the climate system might be fast (e.g., a sudden cooling due to airborne volcanic ash reflecting sunlight), slow (e.g. thermal expansion of warming ocean water), or a combination (e.g., sudden loss of albedo in the arctic ocean as sea ice melts, followed by more gradual thermal expansion of the water). Therefore, the climate system can respond abruptly, but the full response to forcing mechanisms might not be fully developed for centuries or even longer.

This has been considered as the most pressing environmental issue. Climate change is real and it is influenced by human activities through the production of green house gases such as methane and carbon dioxide. Global warming is necessitated by the ability of our ecosystem to respond to climate change due to compromised environment.

Humanity has released sufficient quantities of greenhouse gases into the atmosphere over the last century that we are now starting to feel the effects of an inevitably warmer world. Pronounced droughts, floods, wildfires, and storms are expected more frequently, rising seas will inundate coastlines, and climate patterns will be reconfigured around the planet. Agricultural zones will shift and water may become scarce in many areas prompting mass migrations, great social upheaval, collapsing economies, and wars. Humanity is already committed to a great deal of change in our global climate, but reducing greenhouse gas production and creating more efficient technologies and production systems now will benefit future generations and help us back away from thresholds of irreversibly harsh conditions. We can help other species adapt locally to changing climates by protecting blocks of natural habitat that extend up mountains and pockets of habitat that will retain cooler and moister conditions, such as shady slopes and riverside habitats [естественная среда обитания].

Дата добавления: 2015-11-16