If you want to measure the rate at which global temperatures are rising, then the world’s oceans are perhaps the best places to observe. This is not only due to the fact that Earth’s surface is more than 70% water-covered, but also because ocean water absorbs 90% or more of Earth’s excess heat. Heat energy captured by ocean water is known as “ocean heat content”, which stores that heat for indefinite periods of time.
Ocean Heat Content
Because ocean water soaks up high proportions of atmospheric heat, they are essential for regulating Earth’s climate. Most of the ocean heating is stored at depths between 0 – 700 meters. Air would warm more rapidly without the ocean’s immense heat trapping capacity. Consequently, heat content builds near oceanic surfaces as they take on increasing amounts of heat.
Average Global Temperature by Year
A new analysis authored by 23 researchers that was published in the journal Advances in Atmospheric Sciences uses data across seven ocean basins to assess world ocean warming trends. The study titled, “Another Record: Ocean Warming Continues through 2021 despite La Niña Conditions”, finds that ocean waters have been monotonously increasing in temperature since the year 1958, and that the rate of change sharply quickened toward the end of the 1980s, with 2021 containing more heat energy than any other year on record since recordings began sixty years ago.
Was 2021 the Warmest Year On Record?
With this, 2021 beat the previous record set by 2020 as the year with the most heat energy in world oceans. The team used preexisting sets of data from various measurement devices in conjunction with climate model simulations to prove the accelerated rate of ocean warming in recent decades. It is then inferred that the relatively recent temperature spikes are mainly attributable to increased greenhouse gas concentrations brought on by human activity. The analysis asserts that “the increased concentrations of greenhouse gases in the atmosphere from human activities trap heat within the climate system and result in massive changes in the climate system”.
Is the Climate Rising?
The study lists 2018, 2017, 2019, 2020, and 2021 (in order from least hot to most hot) as the hottest five years of the global ocean since the year 1955. These 5 years, which are quite recent and in close proximity to one another. This suggests that mean temperatures are approaching new highs.