As various regions around the world, including India, endure severe heatwaves exacerbated by the El Niño phenomenon, the oceans are experiencing significant changes as well. Recent data analysis has shown that ocean surface heights are rising at increasingly rapid rates.
Significant Annual Increase in Sea Levels
The global average sea level rose by 0.76 centimeters between 2022 and 2023, a substantial increase compared to previous years. Experts attribute this notable jump to the warming climate and the intensified El Niño conditions.
Long-term Observations Highlight Persistent Rise
NASA‘s comprehensive analysis, leveraging over 30 years of satellite data starting from 1992, highlights a significant and continuous rise in global sea levels. Data from the Sentinel-6 Michael Freilich mission, launched in November 2020, indicates a total increase of approximately 9.4 centimeters since 1993. The rate of sea level rise has also accelerated, from an average of 0.18 centimeters per year in 1993 to the current rate of 0.42 centimeters per year.
Projections for Future Sea Level Rise
Nadya Vinogradova Shiffer, director of NASA’s sea level change team, forecasts an additional rise of 20 centimeters by 2050. This projected increase would double the change observed over the past century, significantly escalating the risk and impact of global flooding.
Seasonal Climate Phenomena and Their Effects
Sea levels are also influenced by seasonal climate phenomena such as La Niña and El Niño. La Niña, characterized by cooler Pacific waters, tends to lower sea levels by redirecting rain from the ocean to the land. Conversely, El Niño, marked by warmer Pacific waters, raises sea levels by returning more rain to the ocean. Although these fluctuations are temporary, they are superimposed on the long-term trend of rising sea levels driven by global warming.
Advanced Techniques for Measuring Sea Level Changes
Researchers employ radar altimeters to measure sea levels, using microwave signals bounced off the ocean surface. This data is refined with information from tide gauges and additional satellite measurements. The detailed record, enriched by international collaboration and technological advancements, enables scientists to understand global sea level changes comprehensively. This combined dataset includes ocean temperature variations, ice loss, and land movement, offering a holistic view of the factors influencing sea level rise.
The continuous rise in sea levels underscores the urgent need for addressing climate change and mitigating its impacts on both the environment and human societies.