The latest science on climate change

Sub : Geo

Sec: Climatology

Context:

The latest climate research highlights that global warming is progressing faster than expected, with a record-breaking year for global temperatures in 2024.
The critical threshold of 1.5°C of warming above pre-industrial temperatures may already have been surpassed, based on new data from Antarctic ice cores.

The 1.5°C Threshold:

A critical and often cited temperature threshold is 5°C above pre-industrial levels.
This is considered a tipping point beyond which the effects of climate change become severe and irreversible.
Recent research, based on an analysis of 2,000 years of atmospheric gas trapped in Antarctic ice cores, suggests that the world may have already crossed this 1.5°C threshold.
Scientists typically use the 1850-1900 period as the baseline to measure temperature changes, new findings suggest that using a longer pre-industrial baseline (spanning from the year 13 to 1700) shows a warming of 49°C by 2023.

Weakening of AMOC:

The Atlantic Meridional Overturning Circulation (AMOC) plays a vital role in keeping European winters milder by transporting warm water from the tropics to the North Atlantic.
However, AMOC has been weakening for decades, with studies indicating a 15% reduction in its strength since 1950.

Coral Bleaching and Ocean Warming:

The world is currently experiencing its fourth and largest mass coral bleaching event.
Scientists fear that many of the world’s coral reefs have reached a point of no return, with ongoing ocean warming exacerbating the situation.
Ocean warming is also contributing to more intense storms, with some tropical storms increasing in strength within hours and leaping over strength categories.

Increased Wildfires:

Global warming is contributing to the intensification of wildfires. The increased frequency and severity of wildfires are linked to higher temperatures, reduced rainfall, and drier conditions in forests.
In 2024, the Amazon rainforest faced its worst and most widespread drought since records began in 1950, with river levels sinking to historic lows.

Carbon Absorption Capacity:

Forests globally are facing difficulties in absorbing carbon dioxide from the atmosphere.
A study published in July 2024 revealed that forests were not able to absorb as much carbon as in previous years.
The loss of this natural carbon sink further exacerbates the climate crisis by reducing the planet’s ability to mitigate the effects of rising CO2 levels.

Increased Volcanic Activity:

Climate change may even be influencing volcanic eruptions. In Iceland, scientists have observed that rapid glacier retreat appears to be triggering volcanic activity.
As glaciers melt, they exert less pressure on the Earth’s crust and mantle, which can lead to increased volcanic eruptions.