Changes in the Earth's climate may influence the melting of Antarctic ice. Climate models, or computer simulations of climate, that do not include these changes may underestimate the impact on global sea level rise, says a new study from Pennsylvania State University.
Despite the certainty that the increase in the planet's temperature causes glaciers to melt, scientists still seek to know how the variation in climate alters and accelerates this process.
New projections consider variations in climate
Climate changes annually, and meteorology works with its decade, century, or millennium average to understand the Earth's climate trend.
Especially in Antarctica, the climate is unstable and complex. Ocean currents and changes in the atmosphere, such as precipitation and storms that occur there, must be considered as climate fluctuations.
READ ALSO : Climate change is making flowers change colour
Thus, the novelty that this study brings is to consider these annual and decadal variations of climate in influencing the melting that occurs in Antarctica.
To study these climate fluctuations, scientists looked at sets of simulations. Each simulation started with small differences in climate conditions. From these differences, variations happened, causing different climate responses.
The scientists applied the data generated from the simulations to three-dimensional models on Antarctic glaciers. They found that atmospheric conditions had the most immediate impact on ice melt. However, oceanic conditions also had impacts that must be considered.
As a final result, the models that considered climate variations had extra predictions of sea level rise between 7 and 11 centimeters by the year 2100, while the models that did not include climate variations projected rise between 27 and 38 centimeters for the same period.
Every weather event that happens in Antarctica, like storms and hurricanes, is related to this extra rise in sea level. They can accelerate the melting of glaciers in the region, according to Chris Forest, a professor and researcher at Pennsylvania State University.
Greater data reality brings warning for scientists
Because it is a complex system, making climate projections for the Antarctic continent requires thousands of computer simulations. Therefore, current models test changes in climate from the decades-long average in temperature.
However, this process can mask the results when it does not take into account annual variations. And, in this way, it can reduce the average high temperatures that cause glaciers to melt.
In fact, this study showed that models that did not consider the annual and decadal changes that happen in Antarctica delayed glacier retreat by up to 20 years and underestimated sea level rise.
Thus, by including annual and decadal variations in the models, it is possible to observe more numbers of warm days reaching ice melt levels.
The extra Antarctic ice melt predicted in the models could impact weather events across the Earth, such as increased occurrence of hurricanes and storms, as well as warning that reports and research on climate change are underestimating global sea level rise, which may be increasing faster than predicted.