During the first pulse of increasing atmospheric CO2 at the beginning of the last deglaciation the carbon-13 ratio dropped precipitously indicating that a source of the CO2 was a large pool of carbon of organic origin. Comparison with other data including the atmospheric carbon-14 record point at outgassing from Southern Ocean deep water as the source of the CO2 increase in this early period of the deglaciation.
A recent study, published in Nature, reports on how anonymized data from three quarter of a million global smart phones was used to detect and map physical inactivity around the world. The study is an outstanding example of the type of scientific analyses that is possible using human beings as sensors.
It is known that orbital forcing is involved in glacial/deglacial cycles but is insufficient by itself to explain the glacial/deglacial cycles. This study argues that a biological feedback mechanism kicks in when a threshold is reached and together with orbital forcing results in the sustained and rapidly increasing CO2 and surface temperature of a deglaciation.
A reanalysis of the effect of black carbon emissions has found that it is second only to carbon dioxide emissions in its warming impact on the climate. Together carbon dioxide, black carbon, and methane emissions represent the anthropogenic sources with the largest impact on Earth’s climate.