Climate Change Accelerates Ocean Warming, Says New Research
We have known for a while that our planet is gradually becoming hotter. Man-made activities have definitely helped increase the generation of carbon dioxide, which in turn traps heat. It’s the greenhouse effect that warms the globe slowly but surely. High amounts of that heat winds up in our oceans, messing up natural currents and bringing chaos in aquatic ecosystems. But until recently, we didn’t know exactly how fast does the ocean warming occur.
Thanks to a new research published in Science Advances, we found out that all of this negative activity is happening much faster than scientists had previously estimated. In fact, the warming rate is around 13 percent faster, raising more red flags about climate change. The research team has discovered a new way to quantify Earth’s warming over the past 56 years.
While fossil fuels have many favorable purposes for us humans, they also have a destructive side effect. Using them adds CO2 to the atmosphere at alarming rising rates. This 40 percent increase, which occurred mostly since 1980, traps more heat, thus warming the whole planet.
Measuring Ocean Warming
However, there are some vital questions that require urgent answers. For example, we need to know Earth’s warming rate and how much it accelerates over time. More information regarding the ocean warming could help governments make smart decisions to handle this issue appropriately. A whopping 90 percent of the trapped heat transfers into our oceans, which gives us one of the most significant measurements of climate change.
According to scientists, however, it’s not that easy to determine the ocean’s temperature. In the past, researchers used expendable bathythermographs to gather data. Deployed along major shipping routes, these devices picked up data via various sensors. However, it was quite a hassle to put together their calculations, which represented a major obstacle in accurately quantifying the history of ocean warming.
However, a new kind of measurement device has been deployed in 2005. The Argo float system (read more about it here) uses a fleet of about 3,800 floats to collect temperature data. Thanks to its advanced technology, the Argo float can autonomously change location in the ocean waters, reaching depths of around 2000 meters. Rising to the ocean surface allows the device to send the collected data wirelessly to satellites.
Correcting Ocean Temperature Data
John Abraham, a co-author of the study and a professor of thermal and fluid sciences at the University of St. Thomas School of Engineering, explained how his team revised and corrected the data from 1960 to 2015. He explained it involved adjusting data bias, data extrapolation, employing progressive climate computer models, and matching the previous statistics to recently collected temperatures.
Therefore, the research team is quite confident they can now draw a rather accurate ocean heat map. Various innovative steps were required to improve our estimates of ocean warming. Once the team corrected known biases and miscalculated measurements, it was easier to apply the new temperature data to larger areas. The new map uses a single measurement as representative of a larger area around the analysis site.
The same scientists conducted a previous experiment which compared actual measurements to climate computer models. On average, their results showed an exceptional agreement. But the recent paper they published addresses more nuanced issues. For instance, the advanced measurement and data collection devices could show the location of the highest amount of warming (in the southern oceans). Apparently, the heating up in the Atlantic and Indian Oceans has occurred only recently.
Point of No Return?
Extending the techniques back to the 1950s allowed the scientists to observe the way the rate of global warming has accelerated over time. Probably the study’s most unsettling discovery is the fact that ocean warming occurs around 13 percent faster than our previous estimates led us to believe. And that spells trouble for other natural phenomena. For example, warmer oceans cause the accelerated thawing of the massive polar ice sheets.
In turn, this contributes to rising sea levels. Recent data revealed exposed areas across the globe could experience sea levels rising up to almost 200 feet (61 meters). Moreover, the ocean warming rate is accelerating. In 1992, the water was heating up at twice the rate from 1960. At the same time, the 1990s marked the first time the accelerated warming permeated to depths lower than 700 meters.
According to Lijing Cheng, the main author of the study, ocean data was very sparse. Thanks to the Argo era, however, scientists could fill the major gaps in their observations. The study accepted the challenge, managing to correct the assessments in global ocean heat. Using an advance gap-filling approach, the team accomplished near global coverage in terms of ocean warming data. Researchers were ensured of the reliability of this approach due to repeated evaluations.
John Fasullo, a co-author, added: “This study shows that more heat is likely to have been absorbed by the oceans over the past 50 years than had previously been reported. With upward revisions in our estimates of the climate’s sensitivity to greenhouse gases and the associated resultant sea level rise.”
There’s no refuting these recent findings. Previous models and theoretical findings are consistent with the newest knowledge about ocean warming and the way warmth spreads deeper and deeper in various oceans. In fact, the study published in Science Advances adds even more evidence to the theories blaming man-made activities for climate change. Past warming has scarred the planet’s oceans, and we are just now learning to read the memories they have saved over the years.
Due to these unsettling changes, the atmosphere over the oceans is increasingly warm and moist. In turn, extraordinary storms form much more often, leading to deluges such as the one that recently affected California. Other times, the warming oceans have caused storms that produce “thousand year floods” – such as Hurricane Matthew and the disaster that occurred in the Carolinas. The irregular weather examples could go on and on – the Houston floods in April 2016 or the Louisiana floods in August. It just goes to show that this new level of understanding could have serious consequences.