Image above: Global Water Vapor – Source: NASA: https://earthobservatory.nasa.gov/global-maps/MYDAL2_M_SKY_WV
Readers may recall that we have reported on the massive amount of water vapor that has been injected into the stratosphere by the 2022 eruption of the Hunga-Tonga volcano. A recent study said a 13% increase in stratospheric water mass and a 5-fold increase of stratospheric aerosol load.
Water vapor is by far the strongest greenhouse gas according to NASA, and it stands to reason that the dramatic increase in stratospheric water vapor is having an effect on global temperature.
Water vapor is Earth’s most abundant greenhouse gas. It’s responsible for about half of Earth’s greenhouse effect — the process that occurs when gases in Earth’s atmosphere trap the Sun’s heat.
Dr. Ryan Maue writes on Twitter:
Everything was going fine until mid-March 2023, and then a dramatic 1°C warming spike in a matter of 2-weeks raised global temperatures to the record levels we are at today.
La Nina –> El Nino is certainly important for the Equatorial Pacific temperature increase. But, how is Hunga-Tonga affecting the Southern Hemisphere polar vortex? Not so good with the Antarctic sea ice down there.
And, the Northern Hemisphere is much warmer than normal especially in the Atlantic. How are all those trillions of gallons of water vapor in the stratosphere doing? How much is left, and how many more years of impacts?
Maue provided this graph:
Another metric, the UAH satellite data also shows a spike in recent months, though still not as strong as the 2015/2016 El Nino, it is at least as strong as the 1997/1998 event.
From a recent publication, “Global perturbation of stratospheric water and aerosol burden by Hunga eruption” bold mine:
The eruption of the submarine Hunga volcano in January 2022 was associated with a powerful blast that injected volcanic material to altitudes up to 58 km. From a combination of various types of satellite and ground-based observations supported by transport modeling, we show evidence for an unprecedented increase in the global stratospheric water mass by 13% as compared to climatological levels, and a 5-fold increase of stratospheric aerosol load, the highest in the last three decades.
Figure 6. Global perturbation of stratospheric water vapour and aerosol burden. (A) 372 Evolution of the global MLS stratospheric water vapour mass (3-day averages) between 100 hPa 373 – 1 hPa pressure levels (solid black curve) and climatological (2004-2021 period) annual cycle 374 (dashed curve), the positive and negative anomalies are shown respectively as red and blue 375 shading. (B) Deseasonalized stratospheric water vapour mass anomaly (per cent 3-day averages) 376 for both hemispheres and the whole globe from MLS. The embedded panel shows the evolution 377 of global anomaly in 2022. (C) Stratospheric aerosol optical depth (SAOD) anomalies for the 60⁰ 378 S – 60⁰ N latitude band (monthly averages) from GloSSAC merged satellite record extended using 379 OMPS-LP measurements at 675 nm scaled to 525 nm wavelength using GloSSAC data and SAGE 380 III/ISS measurements at 521 nm converted to 525 nm using SAGEIII-derived Angstrom exponent. 381 The SAOD anomalies are computed with respect to the background level estimated as GloSSAC 382 SAOD average over volcanically-quiescent 1995-2003 period. The embedded panel shows the full 383 time span of SAOD series. The cyan and pink letters indicate the most significant volcanic 384 eruptions and wildfire events respectively (EC – El Chichon, Pi – Pinatubo, Sa – Sarychev, Na – 385 Nabro, Ke – Kelud, Ca – Calbuco, PNE – Pacific Northwest wildfire event, Ra – Raikoke, ANY 386 – Australian New Year wildfire event, HT – Hunga Tonga).
Here is a video worth watching on the issue.
When an underwater volcano in Tonga erupted in January, it belched out more than ash and volcanic gases; it also spewed 58,000 Olympic-size swimming pools’ worth of water vapor into Earth’s atmosphere, a new study finds.
When the Hunga Tonga-Hunga Ha’apai volcano erupted on Jan. 15, it became the most powerful explosion on Earth in more than 30 years, with an equivalent force of 100 Hiroshima bombs. The explosion sent shock waves around the planet, causing the atmosphere to ring like a bell and generating tsunamis that battered nearby coasts. A plume of ash and dust reached higher into the atmosphere than any other eruption on record and triggered more than 590,000 lightning strikes in three days.
In the new study, researchers used data collected by NASA’s Aura satellite to assess the amount of water that was thrust into the stratosphere, the second layer in Earth‘s atmosphere, which extends from 4 to 12 miles (6 to 20 kilometers) up to 31 miles (50 km) above the planet’s surface. The results revealed that 160,900 tons (146,000 metric tons) of additional water vapor had entered the stratosphere since the volcano erupted, reaching a maximum altitude of 33 miles (53 km), which is in the mesosphere, the layer of the atmosphere that extends from the top of the stratosphere to an altitude of 53 miles (85 km).
This makes it the largest and highest injection of water into the stratosphere since satellites began taking measurements.
“We estimate that the excess water vapor is equivalent to around 10% of the amount of water vapor typically residing in the stratosphere,” which is the biggest increase scientists have ever seen, researchers wrote in the new paper, published online July 1 in the journal Geophysical Research Letters. The water vapor may remain in the stratosphere for around half a decade, the researchers wrote.
It is not totally surprising that the Tonga eruption injected a large amount of water vapor into the atmosphere, considering the explosion ignited around 492 feet (150 meters) below the ocean’s surface, the researchers said. When the volcano erupted, seawater that came into contact with erupting magma was rapidly superheated, which resulted in large amounts of “explosive steam,” they wrote. This is one of the main reasons the explosion was so powerful. However, this is the first time the amount of water has been accurately measured, and it turned out to be much more than scientists had expected.
Normally, big volcanic eruptions release large amounts of ash and gases, such as sulfur dioxide, which can create reflective compounds in the atmosphere. These volcanic byproducts can block sunlight from reaching the planet’s surface, which can cool the atmosphere. However, the Tonga eruption produced surprisingly low levels of sulfur dioxide compared with similarly sized explosions, and most of the ash it ejected quickly fell to the ground.
As a result, experts initially estimated that the underwater explosion would have minimal effects on Earth’s climate. But these estimates were based on the amount of ash and gases that the volcano emitted and did not account for all of the excess water vapor, which could be just as problematic.
This excess water, the researchers warned, could have a radiating effect that could warm the atmosphere much as greenhouse gases do. Because the water is likely to stick around longer than other volcanic gases, like sulfur dioxide — which normally fall out of the atmosphere within two to three years — the water’s warming effect will likely outlast any cooling effects the gases create.
This means the Tonga explosion will likely be the first eruption on record to cause a warming effect, rather than a cooling effect, on the planet, researchers wrote.
The researchers also pointed out that such a sharp increase in water vapor could decrease the amount of ozone in the stratosphere, thus potentially weakening the ozone layer that protects life on Earth from damaging ultraviolet radiation from the sun. Stratospheric water, or H2O, can break down into OH ions over time. Those ions could react with ozone, which is made of three oxygen atoms, to create water and oxygen. However, it is unclear how this will affect the ozone layer as a whole, researchers wrote.
However, the researchers also think the increased water vapor could decrease the amount of methane in the atmosphere, which is one of the main greenhouse gases responsible for climate change. The same OH ions that react with ozone can also react with methane to produce water and a methyl radical (methane with one less hydrogen atom), which traps much less heat in the atmosphere than methane. Hopefully, this potential reduction in methane might offset some of the warming caused by the water vapor, researchers wrote.
However, the study authors think it’s still too early to predict the exact climatic effects of the Tonga eruption. “It is critical to continue monitoring volcanic gases from this eruption and future ones to better quantify their varying roles in climate,” the researchers wrote.
Originally published on Live Science.