Search results
Results From The WOW.Com Content Network
Also called global warming denial. climate change feedback A natural phenomenon that may increase or decrease the warming that eventually results from a change in radiative forcing. climate change mitigation approaches to limit global warming, primarily by the substitution of fossil fuels with low-carbon sources of energy climate commitment How much future warming is "committed", even if ...
Climate change can also be used more broadly to include changes to the climate that have happened throughout Earth's history. [32] Global warming—used as early as 1975 [33] —became the more popular term after NASA climate scientist James Hansen used it in his 1988 testimony in the U.S. Senate. [34] Since the 2000s, climate change has ...
[45] [46] This is equivalent to a change of the semiminor axis of the planet's orbit from 99.95% of the semimajor axis to 99.88%, respectively. [47] Earth is passing through an ice age known as the quaternary glaciation, and is presently in the Holocene interglacial period. This period would normally be expected to end in about 25,000 years. [42]
World leaders are meeting in Paris this month in what amounts to a last-ditch effort to avert the worst ravages of climate change. Climatologists now say that the best case scenario — assuming immediate and dramatic emissions curbs — is that planetary surface temperatures will increase by at least 2 degrees Celsius in the coming decades.
Attenborough points out that because of natural forces, the Earth's temperature has been fluctuating for millions of years, long before humans arrived. However, it is the additional carbon dioxide, leading to an increase in the greenhouse effect , which must also be taken into account.
Cumulative land-use change contributions to CO 2 emissions, by region. [32]: Figure SPM.2b Local vegetation cover impacts how much of the sunlight gets reflected back into space , and how much heat is lost by evaporation. For instance, the change from a dark forest to grassland makes the surface lighter, causing it to reflect more sunlight.
A change in the type, distribution and coverage of vegetation may occur given a change in the climate. Some changes in climate may result in increased precipitation and warmth, resulting in improved plant growth and the subsequent sequestration of airborne CO 2. Though an increase in CO 2 may benefit plants, some factors can diminish this increase.
Suggested causes of ice age periods include the positions of the continents, variations in the Earth's orbit, changes in the solar output, and volcanism. [39] However, these naturally caused changes in climate occur on a much slower time scale than the present rate of change which is caused by the emission of greenhouse gases by human ...