Уур амьсгалын өөрчлөлт: Засвар хоорондын ялгаа

Байгалийн бусад хүчин зүйлүүд, тухайлбал нарны энергийн өөрчлөлт (нарны идэвхижилт), [[галт уул|галт уулын дэлбэрэлт]] нь аж үйлдвэржилтийн өмнөх үеэс одоог хүртэлх хугацаанд маш бага хэмжээний нөлөө үзүүлж байсан байна

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| quote=Recent estimates (Figure 9.9) indicate a relatively small combined effect of natural forcings on the global mean temperature evolution of the seconds half of the 20th century, with a small net cooling from the combined effects of solar and volcanic forcings}}

</ref><ref>{{cite journal | last=Ammann | first = Caspar | coauthors =''et al.'' | date=[[2007-04-06]] | title=Solar influence on climate during the past millennium: Results from ransient simulations with the NCAR Climate Simulation Model | journal=Proceedings of the National Academy of Sciences of the United States of America | volume=104 | issue=10 | pages=3713–3718 | url=http://www.pnas.org/cgi/reprint/104/10/3713 | quote=However, because of a lack of interactive ozone, the model cannot fully simulate features discussed in (44)." "While the NH temperatures of the high-scaled experiment are often colder than the lower bound from proxy data, the modeled decadal-scale NH surface temperature for the medium-scaled case falls within the uncertainty range of the available temperature reconstructions. The medium-scaled simulation also broadly reproduces the main features seen in the proxy records." "Without anthropogenic forcing, the 20th century warming is small. The simulations with only natural forcing components included yield an early 20th century peak warming of ≈0.2&nbsp;°C (≈1950 AD), which is reduced to about half by the end of the century because of increased volcanism.}}