Originally published here.
Nature has intervened in the climate change narrative in a major way with the eruption of the Hunga-Tonga (HT) volcano on the South Pacific seabed. The eruption has experienced minimal exposure in the media because it did not result in major loss of life or property damage. However, it might well prove to be one of the most consequential volcanic events in recent history.
NASA has estimated that the sub-sea eruption expelled sufficient water vapor into the stratosphere to increase stratospheric moisture concentration by approximately 13%, completely overwhelming the minor reduction in stratospheric moisture concentration measured over the past several decades.
Water vapor is the principal greenhouse gas in the atmosphere. A rapid increase of 13% in stratospheric moisture content should have an easily measurable impact on long wave infrared emissions and thus an easily calculable impact on global near-surface temperatures which can be compared to the observed impact. The heated water vapor also transported a significant amount of thermal energy to the atmosphere. The increased water vapor concentration should also ultimately lead to changes in global precipitation.
There has been little or no information provided on other impacts of the eruption. For example, the eruption involved a massive release of both thermal and mechanical energy, both of which contributed to the massive water vapor emission, vaporizing the sea water above the volcano and expelling it to the atmosphere as heated vapor.
However, not all or the water in the immediate vicinity of the volcano was heated sufficiently to vaporize, resulting in a large pool of heated water which should be easily identified and tracked by satellites and the Argo buoys. This pool of heated water might have measurable impacts on the Inter Tropical Convergence Zone and the current El Nino.
The volcanic eruption was a geological event, but it is very likely to influence both weather and climate over a period of several years as the result of the moisture and thermal energy additions to the global atmosphere.
Climate science has a rare opportunity to observe and analyze the effects of a significant step change in atmospheric conditions. Dr. Roy Spencer of the University of Alabama, Huntsville (UAH) reported an increase of 0.35C in the global temperature anomaly in July. He suggested that it was unlikely that this increase was attributable to the developing El Nino, as it is too early in its development. He suggested that it might be the result of the volcanic eruption, at least in part.
Analyzing the effects of the volcanic eruption offers an excellent opportunity to test the projections of the climate models against observations and refine the models to more accurately model the global atmosphere and its response to changing conditions.
There have been suggestions that the recent, rapid increase in North Atlantic Ocean water temperatures might be the result of undersea volcanic eruptions in the Atlantic basin of lesser magnitude than the HT eruption. Analysis of satellite data and data from the Argo buoys might make it possible to confirm this hypothesis and to locate the volcanoes involved.
The HT eruption offers numerous exciting opportunities to advance the state of climate science.