Humans are not the only suspects. The Sun is the primary driver of the climate.
The environmental impact of irrigation includes the changes in quantity and quality of soil and water as a result of irrigation and the ensuing effects on natural and social conditions at the tail-end and downstream of the irrigation scheme.
The impacts stem from the changed hydrological conditions owing to the installation and operation of the scheme. An irrigation scheme often draws water from the river and distributes it over the irrigated area.
As a hydrological result it is found that: These may be called direct effects. Effects on soil and water quality are indirect and complex, and subsequent impacts on natural, ecological and socio-economic conditions are intricate.
In some, but not all instances, water logging and soil salinization can result. However, irrigation can also be used, together with soil drainage, to overcome soil salinization by leaching excess salts from the vicinity of the root zone.
As a hydrological result it is found that the level of the water descends. Irrigation projects can have large benefits, but the negative side effects are often overlooked.
As a result of this massive diversion of freshwater, lakes, rivers, and creeks are running dry, severely altering or stressing surrounding ecosystems, and contributing to the extinction of many aquatic species.
Forannual average soil loss by sheet, rill and wind erosion on non-federal US land was estimated to be On uncultivated cropland, the recent average total soil loss has been 2. The amount due to meat production is some fraction of that due to livestock. However, many estimates use different sectoral assignment of some emissions.
Over the decade throughatmospheric methane content increased by an average of only 6 Tg per year because nearly all natural and anthropogenic methane emission was offset by degradationwhile atmospheric carbon dioxide increased by nearly 15, Tg per year.
Although reduction of methane emissions would have a rapid effect on warming, the expected effect would be small.
Management practices that can mitigate GHG emissions from production of livestock and feed have been identified. Excessive use of vegetation by grazing can be especially conducive to land degradation in dry areas.
There are several published estimates of water use associated with livestock and meat production, but the amount of water use assignable to such production is seldom estimated. However, it would be misleading simply to assign that associated rangeland green water use to beef production, partly because that evapotranspirational use occurs even in the absence of cattle.
Even when cattle are present, most of that associated water use can be considered assignable to production of terrestrial environmental values, because it produces root and residue biomass important for erosion control, stabilization of soil structure, nutrient cycling, carbon sequestration, support of numerous primary consumers, many of which support higher trophic levels, etc.
Withdrawn water from surface and groundwater sources is used for livestock watering, and in some cases is also used for irrigation of forage and feed crops. Impairment of water quality by manure and other substances in runoff and infiltrating water is a concern, especially where intensive livestock production is carried out.
In the US, in a comparison of 32 industries, the livestock industry was found to have a relatively good record of compliance with environmental regulations pursuant to the Clean Water Act and Clean Air Act,  but pollution issues from large livestock operations can sometimes be serious where violations occur.
Various measures have been suggested by the US Environmental Protection Agency, among others, which can help reduce livestock damage to streamwater quality and riparian environments. Non-solar energy is specified, because solar energy is used in such processes as photosynthesis and hay-drying.
Changes in livestock production practices influence the environmental impact of meat production, as illustrated by some beef data. In the US beef production system, practices prevailing in are estimated to have involved 8.
These include waste reduction by conversion of human-inedible crop residues to food, use of livestock as an alternative to herbicides for control of invasive and noxious weeds and other vegetation management,  use of animal manure as fertilizer as a substitute for those synthetic fertilizers that require considerable fossil fuel use for manufacture, grazing use for wildlife habitat enhancement,  and carbon sequestration in response to grazing practices,   among others.Humans interact with the world around us every day, but some of our actions are more harmful than others.
As our population approaches 7 billion people, the effects of human activities on the ecosystem, including the water, air, land and the life that we . Scientists have high confidence that global temperatures will continue to rise for decades to come, largely due to greenhouse gases produced by human activities.
The Intergovernmental Panel on Climate Change (IPCC), which includes more than 1, scientists from the United States and other countries, forecasts a temperature rise of .
Some human activities that cause damage (either directly or indirectly) to the environment on a global scale include human reproduction, overconsumption, overexploitation, pollution, and deforestation, to .
How Much Does Human Activity Affect Climate Change? (and through other human activities, such as clearing land, as well). Or continue to the next section to find out How will climate change affect the world and our society? Further reading. Understanding and Attributing Climate Change (PDF).
Pollution and Habitat Destruction: The Human Factors Contributing To Endangerment & Extinction The Human Factors Contributing To Endangerment & Extinction The Human Factors Contributing To.
Considering the pace of climate change today, scientists can rule out most of those suspects: some happen too slowly to explain current climate change, while others move in small cycles, not long trends, and others only influence the climate in part of the planet.