Query: Multiple lines of independent evidence indicate humidity is rising and provides positive feedback.

Relevant passages:
Confirmation bias <=SEP=> Confirmation bias , also called confirmatory bias or myside bias , David Perkins , a geneticist , coined the term `` myside bias '' referring to a preference for `` my '' side of an issue . is the tendency to search for , interpret , favor , and recall information in a way that confirms one 's preexisting beliefs or hypotheses . It is a type of cognitive bias and a systematic error of inductive reasoning . People display this bias when they gather or remember information selectively , or when they interpret it in a biased way . The effect is stronger for emotionally charged issues and for deeply entrenched beliefs . People also tend to interpret ambiguous evidence as supporting their existing position . Biased search , interpretation and memory have been invoked to explain attitude polarization ( when a disagreement becomes more extreme even though the different parties are exposed to the same evidence ) , belief perseverance ( when beliefs persist after the evidence for them is shown to be false ) , the irrational primacy effect ( a greater reliance on information encountered early in a series ) and illusory correlation ( when people falsely perceive an association between two events or situations ) .   A series of experiments in the 1960s suggested that people are biased toward confirming their existing beliefs . Later work re-interpreted these results as a tendency to test ideas in a one-sided way , focusing on one possibility and ignoring alternatives . In certain situations , this tendency can bias people 's conclusions . Explanations for the observed biases include wishful thinking and the limited human capacity to process information . Another explanation is that people show confirmation bias because they are weighing up the costs of being wrong , rather than investigating in a neutral , scientific way .   Confirmation biases contribute to overconfidence in personal beliefs and can maintain or strengthen beliefs in the face of contrary evidence . Poor decisions due to these biases have been found in political and organizational contexts.Tuchman ( 1984 ) described a form of confirmation bias at work in the process of justifying policies to which a government has committed itself : `` Once a policy has been adopted and implemented , all subsequent activity becomes an effort to justify it '' ( p. 245 ) .   In the context of a discussion of the policy that drew the United States into war in Vietnam and kept the U.S. military engaged for 16 years despite countless evidences that it was a lost cause from the beginning , Tuchman argued :   Wooden-headedness , the source of self-deception is a factor that plays a remarkably large role in government . It consists in assessing a situation in terms of preconceived fixed notions while ignoring or rejecting any contrary signs . It is acting according to wish while not allowing oneself to be deflected by the facts . It is epitomized in a historian 's statement about Philip II of Spain , the surpassing wooden head of all sovereigns : `` no experience of the failure of his policy could shake his belief in essential excellence . '' ( p. 7 )  Folly , she argued , is a form of self-deception characterized by `` insistence on a rooted notion regardless of contrary evidence '' ( p. 209 )

Positive feedback <=SEP=> Positive feedback is a process that occurs in a feedback loop in which the effects of a small disturbance on a system include an increase in the magnitude of the perturbation .  That is , A produces more of B which in turn produces more of A . In contrast , a system in which the results of a change act to reduce or counteract it has negative feedback . Both concepts play an important role in science and engineering , including biology , chemistry , and cybernetics .   Mathematically , positive feedback is defined as a positive loop gain around a closed loop of cause and effect .  That is , positive feedback is in phase with the input , in the sense that it adds to make the input larger .  Positive feedback tends to cause system instability . When the loop gain is positive and above 1 , there will typically be exponential growth , increasing oscillations , chaotic behavior or other divergences from equilibrium . System parameters will typically accelerate towards extreme values , which may damage or destroy the system , or may end with the system latched into a new stable state . Positive feedback may be controlled by signals in the system being filtered , damped , or limited , or it can be cancelled or reduced by adding negative feedback .   Positive feedback is used in digital electronics to force voltages away from intermediate voltages into ' 0 ' and ' 1 ' states . On the other hand , thermal runaway is a positive feedback that can destroy semiconductor junctions . Positive feedback in chemical reactions can increase the rate of reactions , and in some cases can lead to explosions . Positive feedback in mechanical design causes tipping-point , or ` over-centre ' , mechanisms to snap into position , for example in switches and locking pliers . Out of control , it can cause bridges to collapse . Positive feedback in economic systems can cause boom-then-bust cycles . A familiar example of positive feedback is the loud squealing or howling sound produced by audio feedback in public address systems : the microphone picks up sound from its own loudspeakers , amplifies it , and sends it through the speakers again .

Global warming <=SEP=> Global warming , also referred to as climate change , is the observed century-scale rise in the average temperature of the Earth 's climate system and its related effects . Multiple lines of scientific evidence show that the climate system is warming . Many of the observed changes since the 1950s are unprecedented in the instrumental temperature record which extends back to the mid 19th century , and in paleoclimate proxy records over thousands of years .   In 2013 , the Intergovernmental Panel on Climate Change ( IPCC ) Fifth Assessment Report concluded that `` It is extremely likely that human influence has been the dominant cause of the observed warming since the mid-20th century . '' The largest human influence has been emission of greenhouse gases such as carbon dioxide , methane and nitrous oxide . Climate model projections summarized in the report indicated that during the 21st century the global surface temperature is likely to rise a further 0.3 to for their lowest emissions scenario and 2.6 to for the highest emissions scenario . These findings have been recognized by the national science academies of the major industrialized nations and are not disputed by any scientific body of national or international standing .   Future climate change and associated impacts will differ from region to region around the globe . Anticipated effects include warming global temperature , rising sea levels , changing precipitation , and expansion of deserts in the subtropics . Warming is expected to be greater over land than over the oceans and greatest in the Arctic , with the continuing retreat of glaciers , permafrost and sea ice . Other likely changes include more frequent extreme weather events including heat waves , droughts , heavy rainfall with floods and heavy snowfall ; ocean acidification ; and species extinctions due to shifting temperature regimes . Effects significant to humans include the threat to food security from decreasing crop yields and the abandonment of populated areas due to rising sea levels . Because the climate system has a large `` inertia '' and greenhouse gases will stay in the atmosphere for a long time , many of these effects will not only exist for decades or centuries , but will persist for tens of thousands of years .   Possible societal responses to global warming include mitigation by emissions reduction , adaptation to its effects , building systems resilient to its effects , and possible future climate engineering . Most countries are parties to the United Nations Framework Convention on Climate Change ( UNFCCC ) ,  whose ultimate objective is to prevent dangerous anthropogenic climate change . Parties to the UNFCCC have agreed that deep cuts in emissions are required and that global warming should be limited to well below 2.0 C-change relative to pre-industrial levels , with efforts made to limit warming to 1.5 C-change .   Public reactions to global warming and concern about its effects are also increasing . A global 2015 Pew Research Center report showed a median of 54 % consider it `` a very serious problem '' . There are significant regional differences , with Americans and Chinese ( whose economies are responsible for the greatest annual CO2 emissions ) among the least concerned .