2019 – Posted in: Daily News – Tags: IUCN

GLOBAL CLIMATE REPORT

For: Preliminary & Mains

Topics covered: Key findings of the global climate report

The oceans of the world are in deep trouble, according to a report issued at the annual global climate talks in Madrid.

Oxygen levels in the world’s oceans declined by roughly 2% between 1960 and 2010.
The decline, called deoxygenation, is largely attributed to climate change, although other human activities are contributing to the problem.
One study in the journal Science found that water in some parts of the tropics had experienced a 40% to 50% reduction in oxygen.
The mass fish die-offs the coast of California can be seen as the most dramatic example of deoxygenation on the coastal ocean.
This loss of oxygen in the ocean is significant enough to affect the planetary cycling of elements such as nitrogen and phosphorous which are, “essential for life on Earth”.

In deoxygenation, Oceans absorb carbon dioxide and becomes less basic and more acidic, in some places dissolving the shells of aquatic life like clams, mussels and shrimp in what is sometimes called the “osteoporosis of the sea.”
Since the middle of last century, oceans have absorbed 93% of the heat associated with human-caused greenhouse gas emissions, leading to mass bleaching of coral reefs. Warmer water also takes up more space than cooler water. NASA says that this thermal expansion process has caused roughly a third of existing sea level rise.
Global average temperatures have risen 2 degrees Fahrenheit since the late 19th century.
Water holds less oxygen by volume than air does. And as ocean temperatures increase, the warmer water can’t hold as much gas, including oxygen, as cooler water. (It’s why soda tends to go flat faster in the hot summer sun.)
Warming temperatures also affect the ability of ocean water to mix, so that the oxygen absorbed on the top layer doesn’t properly get down into the deeper ocean. And what oxygen is available gets used up more quickly because marine life uses more oxygen when temperatures are warmer.

IUCN is an international organization working in the field of nature conservation and sustainable use of natural resources. It is composed of both government and civil society organisations.
It is involved in data gathering and analysis, research, field projects, advocacy, and education.
IUCN’s mission is to “influence, encourage and assist societies throughout the world to conserve nature and to ensure that any use of natural resources is equitable and ecologically sustainable”.
The organization is best known to the wider public for compiling and publishing the IUCN Red List of Threatened Species, which assesses the conservation status of species worldwide.
IUCN has observer and consultative status at the United Nations and plays a role in the implementation of several international conventions on nature conservation and biodiversity.