Query: Humans are too insignificant to affect global climate

Relevant passages:
Holocene extinction <=SEP=> The Holocene extinction , otherwise referred to as the Sixth extinction or Anthropocene extinction , is the ongoing extinction event of species during the present Holocene epoch , mainly due to human activity . The large number of extinctions spans numerous families of plants and animals , including mammals , birds , amphibians , reptiles and arthropods . With widespread degradation of highly biodiverse habitats such as coral reefs and rainforest , as well as other areas , the vast majority of these extinctions is thought to be undocumented . According to the species-area theory , and based on upper-bound estimating , the present rate of extinction may be up to 140,000 species per year , making it the greatest loss of biodiversity since the Cretaceous -- Paleogene extinction event .   The Holocene extinction includes the disappearance of large land animals known as megafauna , starting at the end of the last Ice Age . Megafauna outside of the African continent , which did not evolve alongside humans , proved highly sensitive to the introduction of new predation , and many died out shortly after early humans began spreading and hunting across the Earth ( additionally , many African species have also gone extinct in the Holocene ) . These extinctions , occurring near the Pleistocene -- Holocene boundary , are sometimes referred to as the Quaternary extinction event .   The arrival of humans on different continents coincides with megafaunal extinction . The most popular theory is that human overhunting of species added to existing stress conditions . Although there is debate regarding how much human predation affected their decline , certain population declines have been directly correlated with human activity , such as the extinction events of New Zealand and Hawaii . Aside from humans , climate change may have been a driving factor in the megafaunal extinctions , especially at the end of the Quaternary .   The ecology of humanity has been noted as being that of an unprecedented `` global superpredator '' that regularly preys on the adults of other apex predators and has worldwide effects on food webs . Extinctions of species have occurred on every land mass and ocean , with many famous examples within Africa , Asia , Europe , Australia , North and South America , and on smaller islands . Overall , the Holocene extinction can be characterized by the human impact on the environment . The Holocene extinction continues into the 21st century , with meat consumption , overfishing , ocean acidification and the amphibian crisis being a few broader examples of an almost universal , cosmopolitan decline in biodiversity . A ballooning human population along with profligate consumption are considered to be the primary drivers of this rapid decline .

Human impact on the environment <=SEP=> Human impact on the environment or anthropogenic impact on the environment includes impacts on biophysical environments , biodiversity , and other resources . The term anthropogenic designates an effect or object resulting from human activity . The term was first used in the technical sense by Russian geologist Alexey Pavlov , and was first used in English by British ecologist Arthur Tansley in reference to human influences on climax plant communities . The atmospheric scientist Paul Crutzen introduced the term `` Anthropocene '' in the mid-1970s . The term is sometimes used in the context of pollution emissions that are produced as a result of human activities but applies broadly to all major human impacts on the environment .

Human <=SEP=> Modern humans ( Homo sapiens , primarily ssp . Homo sapiens sapiens ) are the only extant members of Hominina tribe ( or human tribe ) , a branch of the tribe Hominini belonging to the family of great apes . They are characterized by erect posture and bipedal locomotion ; high manual dexterity and heavy tool use compared to other animals ; and a general trend toward larger , more complex brains and societies .   Early hominins -- particularly the australopithecines , whose brains and anatomy are in many ways more similar to ancestral non-human apes -- are less often referred to as `` human '' than hominins of the genus Homo . Several of these hominins used fire , occupied much of Eurasia , and gave rise to anatomically modern Homo sapiens in Africa about 200,000 years ago . They began to exhibit evidence of behavioral modernity around 50,000 years ago . In several waves of migration , anatomically modern humans ventured out of Africa and populated most of the world .   The spread of humans and their large and increasing population has had a profound impact on large areas of the environment and millions of native species worldwide . Advantages that explain this evolutionary success include a relatively larger brain with a particularly well-developed neocortex , prefrontal cortex and temporal lobes , which enable high levels of abstract reasoning , language , problem solving , sociality , and culture through social learning . Humans use tools to a much higher degree than any other animal , are the only extant species known to build fires and cook their food , and are the only extant species to clothe themselves and create and use numerous other technologies and arts .   Humans are uniquely adept at utilizing systems of symbolic communication ( such as language and art ) for self-expression and the exchange of ideas , and for organizing themselves into purposeful groups . Humans create complex social structures composed of many cooperating and competing groups , from families and kinship networks to political states . Social interactions between humans have established an extremely wide variety of values , social norms , and rituals , which together form the basis of human society . Curiosity and the human desire to understand and influence the environment and to explain and manipulate phenomena ( or events ) has provided the foundation for developing science , philosophy , mythology , religion , anthropology , and numerous other fields of knowledge .   Though most of human existence has been sustained by hunting and gathering in band societies , increasing numbers of human societies began to practice sedentary agriculture approximately some 10,000 years ago , domesticating plants and animals , thus allowing for the growth of civilization . These human societies subsequently expanded in size , establishing various forms of government , religion , and culture around the world , unifying people within regions to form states and empires . The rapid advancement of scientific and medical understanding in the 19th and 20th centuries led to the development of fuel-driven technologies and increased lifespans , causing the human population to rise exponentially . Today the global human population is estimated by the United Nations to be near billion .

Climate system <=SEP=> Earth's climate arises from the interaction of five major climate system components: the atmosphere (air), the hydrosphere (water), the cryosphere (ice and permafrost), the lithosphere (earth's upper rocky layer) and the biosphere (living things). Climate is the average weather, typically over a period of 30 years, and is determined by a combination of processes in the climate system, such as ocean currents and wind patterns. Circulation in the atmosphere and oceans is primarily driven by solar radiation and transports heat from the tropical regions to regions that receive less energy from the Sun. The water cycle also moves energy throughout the climate system. In addition, different chemical elements, necessary for life, are constantly recycled between the different components. The climate system can change due to internal variability and external forcings. These external forcings can be natural, such as variations in solar intensity and volcanic eruptions, or caused by humans. Accumulation of heat-trapping greenhouse gases, mainly being emitted by people burning fossil fuels, is causing global warming. Human activity also releases cooling aerosols, but their net effect is far less than that of greenhouse gases. Changes can be amplified by feedback processes in the different climate system components.