Influence of Relative Humidity and Clouds on the Global Mean Surface Temperature

Abstract

The explanation for climate change is still searching for an experimental proof and the most important question is whether climate change is anthropogenic. According to the Intergovernmental Panel on Climate Change IPCC global warming is mostly man made due to the increasing CO2 concentration. In this work we study the contributions of humidity and clouds to the surface temperature. We will show that changes of relative humidity or low cloud cover explain the major changes in the global mean temperature. We will present the evidence of this argument using the observed relative humidity between years 1970 and 2011 and the observed low cloud cover between years 1983 and 2008. One percent increase in relative humidity or in low cloud cover decreases the temperature by 0.15 °C and 0.11 °C, respectively. In the time periods mentioned before the contribution of the CO2 increase was less than 10% to the total temperature change.

No experimental evidence for the significant anthropogenic climate change

“…These experimental observations indicate that 1 % increase of the low cloud cover fraction decreases the temperature by 0.11°C. This number is in very good agreement with the theory given in the papers [3,2,4]. Using this result we are able to present the natural temperature anomaly by multiplying the changes of the low cloud cover by −0.11°C/%.…”

“…The first and second term are the contributions of CO 2 [5] and the low clouds, respectively. Using the sensitivity ∆T 2CO2 = 0.24°C derived in the papers [3,2,4] the contribution of greenhouse gases to the temperature is only about 0.04°C according to the first term in the above equation. This is the reason why we do not see this small increase in temperature in Figure 3, where the temperature anomaly is quite noisy with one month time resolution.…”

“…If we pay attention to the fact that only a small part of the increased CO 2 concentration is anthropogenic, we have to recognize that the anthropogenic climate change does not exist in practice. The major part of the extra CO 2 is emitted from oceans [6], according to Henry's law. The low clouds practically control the global average temperature.…”

Estimation of the terms acting on local 1 h surface temperature variations in Paris region: the specific contribution of clouds

“…Clouds are well known to directly modify near-surface temperatures and other near-surface variables on multiple timescales (Parding et al, 2014;Broeke et al, 2006;Kauppinen et al, 2014). Hence the second objective of the current study is to understand the specific role of clouds and their associated characteristics in hourly temperature variations.…”

Late Twentieth-Century Warming and Variations in Cloud Cover

“…Herman et al [6] also discussed global cloud cover but dealt mainly with surface reflectivity at 340 nm. Kauppinen et al [7] discussed the impact of both humidity and cloud cover on the global mean surface temperature. Eastman and Warren discuss long-term trends in cloud over sea [8] and land [9].…”