Record Average Ocean Surface Temperatures Could Trigger Explosive Global Methane Release

Methane hydrate is a flammable ice-like form of methane which is present in large quantities under permafrost and deep beneath the ocean. New data showing oceans have reached record surface temperature levels, along with other findings, suggest the "methane hydrate bomb" is about to to let go. Image: U.S.Geological Survey

Reaching this new high average sea surface temperature, calculated based on samples recorded between 60° North Latitude and 60° South Latitude, is a change that could alter global climate conditions forever.

The temperature change comes at the normal time for maximum ocean surface temperatures, so it is not surprising by itself that this kind of peak might occur at this moment. But it also comes as several other changes are happening in parallel that make this peak far more serious.

In addition to the ongoing temperature increases on the planet due to greenhouse gas emissions trapping and global heating, another factor influencing conditions this year is the passing of the most recent La Niña weather cycle and moving to an El Niño weather cycle possibly by this summer.

The weather pattern known as La Niña manifest with a higher-percentage-than-normal of cold waters present between the Tropic of Cancer and the Tropic of Capricorn. These geographic “boundaries” are located at 23.5° latitude north and 23.5° south of the equator, representing the northernmost and southernmost positions where the sun can be directly overhead.

The cold waters of the La Niña cycle are directed upwards in the tropics by powerful eastward-directed trade winds and ocean currents, in a natural process known as upwelling. When the cold water reaches the surface, they can cause a significant drop in ocean surface temperatures.

Coming along with La Niña is a pattern of lower-than-normal air pressure over the western Pacific region, which in turn brings more rain where it is present. Typically, this results in higher amounts of rain connected with Southeast Asia’s important summer monsoon regions, which have important benefits for water supply and agriculture in India and Bangladesh. It has the downside of bringing with it often torrential rains In Australia, and — because the Pacific current patterns influence the flow of all such wind and ocean conditions — extends its reach with similar rain patterns as far away as in northern Brazil and southeastern Africa.

The particular La Niña cycle we are currently exiting began in September 2020. In just the last twelve months of this cycle, it has made its mark in multiple ways, including reduced rain and drought conditions along the U.S. gulf coast, in the southern part of the U.S. extending all the way to Texas, and in South America, along its west tropical coast and in the pampas areas in the southern part of the continent. This dry pattern, coupled with high heat and strong breezes, is behind the fires currently burning out of control in southern Chile.

In Asia, its presence was a direct cause of the heavy rainfall which wiped out farmlands and homes throughout India in July of last year. It also is behind the record-setting rainfall which deluged Pakistan from late August through September 2022. Those waves of rain forced millions of people to flee their homes and destroyed approximately half the crop-growing regions in the country.

The record high ocean surface temperature at this time is problematic because it runs counter to how a typical La Niña event should be showing up. This is especially so as atmospheric and oceanic cycles move into the El Niño phase.

Monthly global temperature anomalies (compared to their 20th century average) since 1950, and the influence of the El Niño - Southern Oscillation (ENSO) phenomenon. (Citation: NOAA National Centers for Environmental Information, Monthly Global Climate Report for February 2023, published online March 2023, retrieved on March 23, 2023 from https://www.ncei.noaa.gov/access/monitoring/monthly-report/global/202302/supplemental/page-4) Image: NOAA National Centers for Environmental Information

The El Niño period starts with ocean surface temperatures in the tropical Pacific which are warmer than usual, and with east winds which are less powerful than the corresponding La Niña ones. Without those strong trade winds coming from the Americas, the upwelling to bring the colder waters from below upwards does not happen. That allows the ocean water to become considerably hotter than normal, and on top of ocean heating which is caused by the climate crisis.

On its own, based on historical data, an El Niño could cause global temperatures to rise by at least 0.5° C by the time it reaches its peak. But the El Niño ahead is now looking like it will be coming along more quickly and with higher ocean temperature warming than usual. If that happens, in addition to what it means for other planetary conditions, it could drive Arctic temperatures, continued polar ice melt, and accelerated thawing of permafrost to set new records.

One metric which suggests this, is the all-time-high sea surface temperature measured on March 16.

In addition to that, another temperature metric measured on March 15, 2023, provides even more proof of what is about to happen.

On that date, remote monitoring showed that sea surface temperatures measured off the North American east coast were running approximately 13.8° C (24.8° F) higher compared to the average measured from 1981-2011. Temperatures were also showing similar anomalies in the Pacific Ocean.

Then, on top of both those discoveries, a series of temperature samples made by the fleet of Argo floating temperature and salinity devices revealed something else relevant. It showed indirect proof of the presence of a sizable “cold freshwater lid” forming in the North Atlantic. That term refers to a region where rain and ice melt, in this case coming from the Arctic, form a mass of freshwater which is colder than the ocean beneath and is trapped above it, both because of its sources and because it does not mix readily with high-salinity ocean water below.

These come in addition to data gathered just released over a year ago by the European Copernicus Climate Change Service and other agencies, which showed the Greenland Sea saw its lowest minimum sea ice extent on record. This means more freshwater pouring off Greenland. 

This, combined with stronger-than-normal winds which mirror the oceanic regions below in the Atlantic Ocean, have the power to drive hotter-than-normal waters from the Gulf Stream at more rapid rates than usual up to the Arctic. There they dive beneath the cold freshwater lid, where the pressures and current speeds cause an extremely warm pocket of saltier-than-normal seawater to collect underneath the lid and surge northward far into the Arctic.

That resultant hot and high-salt oceanic current will eventually have devastating impacts on the Arctic. When it hits frozen land areas deep under the ocean, it could cause the extensive methane hydrate crystals present there to release their methane in gas form in rapid breaches. As the gas bubbles upwards, the explosive force of the release, created as the volume of the material expands from 160 to 180 times what it was as a solid, can cause other methane hydrate pockets to break apart, in a domino effect. This could cause a massive injection of methane into the atmosphere before summer is over, in turn resulting in adding a dangerous new layer of the most potent heat-trapping gas in existence, running between 30 and 80 times as damaging as carbon dioxide in equivalent energy it can hold close to the earth’s surface.

That this was getting closer than ever to happening was already becoming evident in findings disclosed over a year ago by the European Copernicus Climate Change Service and other agencies. Those showed the overall rate of methane was accelerating, to a rate measured in January 2022 at 16.3 ppb/year. That already represented an increase of 3.6% from the values reported just two years earlier.

Depiction of the vast range of permafrost in the Northern Hemisphere which could be unleashed as ocean temperatures warm up and move further north. (Image provided under Creative Commons license from the original source, via GRID Arendal.)

The next domino to fall as the hot high-salinity waters burst forth into the northern Arctic would be accelerating melting of the vast Arctic permafrost, which would then lead to further concentrated methane releases and more atmospheric and ground heating and a massively destructive feedback loop.

The East Siberian Arctic Shelf (ESAS), located just north of the easternmost regions of Russia, is among the most vulnerable areas there. Its high-risk profile with regards to rapid melting combines shallow water areas which could superheat quickly, along with extensive submerged permafrost which would almost certainly be unlocked.

The ESAS makes up a quarter of the Arctic shelf area , with an average depth of only 58 meters (190 feet) and significant riverine input. (Image provided under Creative Commons license from the source: Image: GRID Arendal.)

Scientists believe the explosive release of the methane from all these combined conditions could cause average temperatures on the planet to rise by from 0.5° - 1.0° within just a few years. Increased heat trapping could push that further, to as much as 3.0° C in ten to fifteen years. Such temperature changes would also trigger species-selective mass extinctions in multiple areas of the world, not to mention rapid sea level rise, the growing geographic spread of drought, and extreme weather cycles the planet has never seen since homo sapiens roamed the planet.

Add to that the multiplicative effect of perhaps the most powerful El Niño cycle in recorded history, and even more damaging events might come to pass. The combined impact of superheated oceanic currents driven according to the El Niño cycle, and one can expect rapid disruption of everything from tropical rainfall systems and Asian monsoons, to accelerating drought conditions on all continents on the globe.

It could take slightly longer for that to push the Antarctic Ice Shelves to crack apart as they have threatened to for years, but that too will eventually happen.

And even if all of this were not to occur this year, the data shows the trigger has been set for it. Indicators for how bad it could be and how fast will be evident soon, in the form of continued record high surface ocean temperatures, early heat records being broken along the edge of the Arctic circle and especially in Siberia, with satellite measurements demonstrating explosive methane releases there as well.

The wildcard in all this is the Polar Vortex over the North Pole. It was only recently discovered that a plasma vortex sits high above the North Pole which is responsible for the Polar Vortex that pulls super cooled air from the upper atmosphere down into the jet stream where is distributed across the Northern Hemisphere. With this cooling system being more active over the past year, there has been cold records set across North American all the way down into Mexico. Few climate scientists are taking this into consideration.