Tag Archives: COP21

Melting Antarctica could double sea level rise

Unabated greenhouse gas emissions could lead to sea level rise twice as high as we had anticipated, according to a recent study published in Nature.

By the end of this century, scientists predict that sea levels could rise by over 2 meters on average. Note that this is a global average, meaning that some areas could see much higher local rises in sea level. For Small Island Developing States, this could mean the end of their existence altogether. The research has been welcomed by the scientific community, who had already raised reservations with regards to what was called “very conservative” estimates of sea level rise caused by a changing climate.

So what has changed, how could we suddenly double sea level rise? The answer lies in complex processes involved in the melting of ice in Antarctica. Previous estimates had failed to take into account accelerated melting caused by disintegrating ice sheets. In fact, scientists had only been able to consider the melting ice shelves due to increased air and water temperatures, and had ignored the impact of surface melt-water and rainfall which can help fracture large chunks of ice.

Thwaites_glacier_NASA
The Thwaites glacier is one of the fastest flowing glaciers off Antarctica. Source: Jim Yungel/NASA

Climate change adaptation has been hailed as the ultimate recourse to prevent negative impacts of sea level rise. For instance, in a number of coastal regions, ecosystem-based adaptation helped by mangroves has been underway for some years already. Mangroves play a significant role in protecting coastal regions from intense storms including typhoons, expected to increase in frequency with climate change. Combined with sea level rise, such storm could be catastrophic, especially in densely populated areas.

Mangrove_Peyri_Herrera_Flickr2
Mangrove forests like these help protect coastal communities against storms and storm surges.

In previous adaptation planning, the unique property of mangroves to “grow soil” had been counted on to mitigate the impacts of rising sea levels. The rate of growth of mangroves was very much in line with previous climate change projections, yet this new data would suggest that these fragile ecosystems would no longer be able to keep up with the increased rate of sea level rise. Hence, millions of the most vulnerable coastal communities will likely have to rethink their adaptation strategies, a very costly endeavour.

So what is the silver lining? If we achieve the targets set in the 2015 Paris Agreement, sea levels will continue to rise, but never to the rate which would occur if Antarctica’s melting was to start accelerating. Coastal communities will still need to adapt, but costs will be reduced and lives will be saved.

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“We must. We can. We did!” Historic Paris Climate Agreement adopted

A historic agreement to tackle climate change and pave the way towards a low carbon, greener and cleaner future has been adopted by 195 nations in Paris.

This was a truly monumental political achievement that was only possible because of the deep urge felt unanimously by all member nations to act on one of the greatest challenges humanity has ever faced; that the climate is changing with disastrous consequences for people all over the world.

The Paris Agreement’s main aim is to limit global warming to well below 2 degrees Celsius by the end of the century and to drive efforts to limit temperature increase to 1.5 degrees.

The 1.5 degree Celsius limit is a significantly safer defence line against the worst impacts of a changing climate.

To reach these ambitious goals will require collaboration in a global scale, with richer nations providing much of the financial and technological means to implement low carbon, green initiatives throughout the world.

French President Francois Hollande told the assembled delegates: “You’ve done it, reached an ambitious agreement, a binding agreement, a universal agreement. Never will I be able to express more gratitude to a conference. You can be proud to stand before your children and grandchildren.”

Over the next few weeks I will be posting about the key implications of this agreement.

 

Details of the Paris Agreement can be found:
[1] http://unfccc.int/meetings/paris_nov_2015/in-session/items/9320.php
[2] http://newsroom.unfccc.int/unfccc-newsroom/finale-cop21

A love poem for the Earth #showthelove

Yesterday was National Poetry Day, so here are some celebrities reading a simple love sonnet. We can protect the planet we love!

“So long as men can breathe, or eyes can see,
So long lives this, and this gives life to thee.”
– Sonnet 18, William Shakespeare

“So long, and thanks for all the fish” … the end of coral reefs?

Leading scientist says that even ambitious greenhouse gas reduction targets will not be able to save the world’s coral reefs.

Professor Peter Sale from the University of Windsor, Canada claims that coral reefs, as they were 50 years ago, cannot be saved from climate change – even if the climate change talks in December this year (COP21) are “wildly successful”.

Professor Sale unveiled the depressing results today at the Goldschmidt conference, a gathering of the world’s top geochemists in Prague.

He said, “Even if Paris is wildly successful, and a treaty is struck, ocean warming and ocean acidification are going to continue beyond the end of this century. This is now serious; I find it very unlikely that coral reefs, as I knew them in the mid-1960s, will still be found anywhere on this planet by mid-century. Instead, we will have algal-dominated, rubble-strewn, slowly eroding limestone benches.”

A bleached coral. These events will become more common with global warming.
A bleached coral. These events will become more common with global warming.

Globally coral reefs are generally found in tropical waters. Not only are they some of the world’s most productive ecosystems they also deliver ecosystem services in tourism, fisheries and coastline protection. The global economic value of coral reefs has been estimated to be US $375 billion per year!

Loss of reefs will be a fatal blow for the animals and communities who rely on them

While the global policy debate has been about trying to limit global warming to 2 degrees by the end of the century, Professor Sale claims that this won’t be enough to save coral reefs.

“I see little hope for reefs unless we embark on a more aggressive emissions reduction plan. Aiming for CO2 at 350ppm, or a total warming of around 1°C is scientifically defendable, and would give reefs a good chance; a number of coral reef scientists have called for this.”

Sale summarised:

“Knowing what we are doing, do we have the ethical right to eliminate an entire ecosystem from this planet? It’s never been done before. But watching as our actions lead to the loss of all coral reefs on the planet is like removing all rainforests. I don’t believe we have that right”.