Natural Causes of Climate Change. Factors primarily responsible for most past climate change: Variations in the Earth\'s orbital characteristics. Atmospheric carbon dioxide variations. Volcanic eruptions Variations in solar output. Volcanoes and Gases.
Sulphur dioxide measurements with spectrometer. Mt San Helens
Collecting Gas Samples at Mt. San Helens
The most abundant gas typically released into the atmosphere from volcanic systems is water vapor (H20), followed by carbon dioxide (C02) and sulfur dioxide (S02). Volcanoes also release smaller amounts of others gases, including hydrogen sulfide (H2S), hydrogen (H2), carbon monoxide (CO), hydrogen chloride (HCL), hydrogen fluoride (HF), and helium (He).
Examples of volcanic gas compositions, in volume percent concentrations(from Symonds et. al., 1994)
Graphs of average temperatures 5 years before and 5 years after the listed various volcanic eruptions. Low temperatures always occur after an eruption (occurring at Month #0). Graph “e.” is a composite of the graphs a.–d. Graph “f.” is the response to the most recent Mt. Pinatubo eruption. (From: Climate Research Unit).
A list of years characterized by low tree-ring densities, with the name of the volcano eruption immediately preceding the tree-ring event indicated in parentheses (n.d. = not determined).
Naggs & Raheem
Tathagata \'Ted\' Dasgupta
The basalt layers in India\'s Deccan Traps could be used to store huge amounts of carbon dioxide. DINODIA IMAGES/ALAMY
Images from Nasa
The solar disk seen by the Yohkoh soft-X-Ray imager, over the time period 1991-1995 (left to right), spanning the descending phase of cycle 23.
Solar irradiation is the amount of energy from solar radiation hitting earth’s surface.