Effect of volcanic activities and CO2 concentration on summer temperature in middle stratosphere, North Hemisphere

Abstract

Successive filtration and comparison show that the stratosphere air temperature in 10 hPa-layer of the Northern Hemisphere (NH) in July continuously increases, which is associated to the increases in greenhouse gases mostly CO 2 , volcanic activities, and solar activity, demonstrating the follows. (a) The increase in CO 2 concentration is largely consistent with that of the stratosphere air temperature in 10 hPa-layer of the NH in July. However, the increase in the air temperature is not in a linear pattern, during which several cooling events interrupt. The cooling events between late 1960s and late 1970s are remarkable ones and so is the one before mid 1990s. Analysis shows that these events are induced by volcanic activities and solar activity. (b) The CO 2 -free variation in the stratosphere air temperature in 10 hPa-layer of the NH is consistent with that of the solar magnetic index. The wave crests and wave troughs of the two curves are consistent in phase, and the curve of solar magnetic index leads the other slightly. In other words, when the solar magnetic pole is southward, a warming in the NH stratosphere corresponds; and on the contrary, the northward solar magnetic pole corresponds to a cooling event. The variation in solar magnetic polarity strongly impacts the variation in the stratosphere temperature.

The Periodicity of Volcano Activity and Its Reflection in Some Climate Factors

“…The 5-year running averaged curve of ground temperature (GT) in Northern Hemisphere (NH) in 1841∼2000 shows that the GT rising trend is basically consistent with CO 2 rising trend [63,64] . Some researchers [65,66] also point out that the NH GT rising is not linearly increasing as that of CO 2 density does, while there are a few cases of temperature cooling.…”

“…The "umbrella effect" of volcanic activities and the "greenhouse effect" of CO 2 density increasing produce the increase of the GT of the NH in recent 100 years. So the 63% variance contribution should include both the contribution of CO 2 density increase and that of the volcanic activities [63,64] .…”

Volcanic Activity Sparks Arctic Oscillation

“…Strong volcanic eruptions [7][8][9][10][11][12][13][14][15] , another natural phenomenon that has an important impact on the Earth's climate, have also captured scientists' attention. A large number of observational studies and numerical Simulation experiments have demonstrated that strong volcanic eruptions, through their stratospheric volcanic dust and aerosols, can signi cantly change the atmospheric radiation budget and affect large-scale and even global climate change [16][17][18][19][20][21][22][23][24][25][26] .Studies of the impact of volcanic activity on the NORTH Atlantic Oscillation have been completed,indicate ,Due to the middle and lower troposphere to sea level Icelandic low pressure and Azores high winter and summer temperature and pressure eld structure characteristics are basically opposite,The parasol effect of strong volcanic eruptions has led to a general drop in temperatures in the northern and southern waters of the North Atlantic, and caused opposite responses in two circulation systems, the Icelandic Low and the Azores high.For example, in winter, the Iceland low pressure system deepens as the isobaric surface of low altitude temperature drops;Azores high is a shallow system in winter,When the low air temperature drops, the high pressure active area is pressurized by sea level and the high pressure system is strengthened,Thus, the reverse phase oscillation of sea level pressure eld between high and low latitudes is caused, which forms or intensi es the widely in uential phenomenon of north Atlantic oscillation.…”