global warming tagged posts

Just 2% of the Great Barrier Reef remains untouched by bleaching since 1998 and 80% of individual reefs have bleached severely once, twice or three times since 2016, our new study revealed on November 4. We measured the impacts of five marine heatwaves on the Great Barrier Reef over the past three decades: in 1998, 2002, 2016, 2017 and 2020. We found these bouts of extreme temperatures have transformed it into a checkerboard of bleached reefs with very different recent histories.

Whether we still have a functioning Great Barrier Reef in the decades to come depends on how much higher we allow global temperatures to rise. The bleaching events we have already seen in recent years are a result of the world warming by 1.2 degrees Celsius since pre-industrial times.

World leaders meetin...

China will aim to hit peak emissions before 2030 and for carbon neutrality by 2060, President Xi Jinping has announced. Mr Xi outlined the steps when speaking via videolink to the UN General Assembly in New York. The announcement is being seen as a significant step in the fight against climate change. 

China is the world’s biggest source of carbon dioxide, responsible for around 28% of global emissions.

With global climate negotiations stalled and this year’s conference of the parties (COP26) postponed until 2021, there had been little expectation of progress on the issue at the UN General Assembly.

However China’s president surprised the UN gathering by making a bold statement about his country’s plans for tackling emissions. 

He called on all countries to achieve a green re...

This summer’s Arctic sea-ice shrank to its second lowest ever extent in the era of satellite observation. The floes withdrew to just under 3.74 million sq km (1.44 million sq miles) last week, preliminary data indicates. The only time this minimum has been beaten in the 42-year spacecraft record was 2012 when the pack ice was reduced to 3.41 million sq km. Shorter autumn days and encroaching cold mean the floes are now starting to regrow.

It’s normal for Arctic sea-ice to expand through the winter each year and then melt back again in the summer, but the September minima, accounting for some variability, are getting deeper and deeper as the polar north warms.

The downward trend since satellites started routinely monitoring the floes is about 13% per decade, averaged across the month...

During the period of global warming at the close of the last ice age, Earth’s sea level did not rise steadily but rather in sharp, punctuated bursts when the planet’s glaciers melted, researchers report.

The researchers found fossil evidence in drowned reefs offshore Texas that showed sea level rose in several bursts ranging in length from a few decades to one century.

“What these fossil reefs show is that the last time Earth warmed like it is today, sea level did not rise steadily,” says coauthor André Droxler, a marine geologist from Rice University. “Instead, sea level rose quite fast, paused, and then shot up again in another burst and so on.

“This has profound implications for the future study of sea-level rise,” he says.

Because scientists did not previously have speci...

Rising temperatures caused by climate change would be catastrophic for countries in Asia and the Pacific by the end of the century – unless countries work to mitigate it, says a report by the Asian Development Bank (ADB) released last month. The report titled “A Region at Risk: The Human Dimensions of Climate Change in Asia and the Pacific” says that under a “business-as-usual” approach to climate change, the impacts for the Asia and Pacific region are catastrophic.

With climate change, food production in the region will become a lot more difficult, causing production costs to increase.

According to a data summary, crops in the Pacific region will be in decline by 2050...

In 2003, researchers declared Coral Castles dead. On the floor of a remote island lagoon halfway between Hawaii and Fiji, the giant reef site had been devastated by unusually warm water. Its remains looked like a pile of drab dinner plates tossed into the sea. Research dives in 2009 and 2012 had shown little improvement in the coral colonies.

Global temperatures are set to rise more than one degree above pre-industrial levels according to the UK’s Met Office. Figures from January to September this year are already 1.02C above the average between 1850 and 1900. If temperatures remain as predicted, 2015 will be the first year to breach this key threshold. The world would then be half way towards 2C, the gateway to dangerous warming.
The new data is certain to add urgency to political negotiations in Paris later this month aimed at securing a new global climate treaty.

Difficult to measure
For researchers, confusion about the true level of temperatures in the 1750s, when the industrial revolution began and fossil fuels became widely used, means that an accurate assessment of the amount the world has warmed since then is very di...