As we say good bye to yet another eventful year, let us prepare to greet a bright new year ahead of us. A lot has happened in 2017. Let us visit some of the major happenings of the year from a climate change perspective.
The year started off with an official confirmation from the National Oceanic & Atmospheric Administration (NOAA) and National Aeronautics and Space Administration (NASA) in January that 2016 was indeed the hottest year ever measured. Just two months later in March, NOAA announced that atmospheric carbon dioxide concentrations were climbing at a record pace for the second year in a row, well above the average annual jump recorded throughout most of the last decade. For perspective, prior to the Industrial Revolution and the large-scale release of greenhouse gases, carbon dioxide concentrations had averaged about 280 ppm. At the time the announcement was made, global carbon dioxide concentrations were resting at about 405 ppm and were expected to continue rising.
Early March is around the time when Arctic sea ice typically reaches its maximum extent. Turns out it was the lowest max extent ever recorded in 2017, reaching just 470,000 square miles. For comparison, the average extent between 1981 and 2010 was about 5.57 million square miles. It's the third year in a row scientists have seen a record winter low in the Arctic. In July, one of the biggest icebergs ever recorded broke from Antarctica's Larsen C ice shelf and began drifting out to sea. Dubbed "A68" by scientists, it contains about a trillion tons of ice. Just a few months later, in September, Antarctica's massive Pine Island Glacier - which already pours about 45 billion tons of ice each year into the ocean - calved an iceberg four times the size of Manhattan, or about 100 square miles.
Multiple studies this year suggested that sea-level rise is occurring faster, or may be more severe in the future, than previous estimates indicate. Some of the studies have suggested that better accounting for some of the physical processes affecting ice loss in Antarctica could double the sea-level rise expected under severe climate change scenarios. An April report from an Arctic monitoring program suggested that previous Intergovernmental Panel on Climate Change estimates for sea-level rise were likely too low. One of the most alarming of these reports published by the Proceedings of the National academy of Sciences of North America found that the rate of global sea-level rise may have nearly tripled since the 1990s!
We always considered forests to be the saviours of the planet for its ability to suck out carbon from the atmosphere. A study published in Nature, suggested that plants worldwide contain about 450 billion metric tons of stored carbon - and that if humans stopped clearing or degrading them, they could potentially store as much as 916 billion tons. For these same reasons, it is also known that tropical forests are also a net carbon source! A study, published this October in Science, found that tropical forests emit about 400 million metric tons of carbon into the air each year, because of deforestation and degradation. 2017 also marks the first time, when some studies concluded that some extreme climate events could not have occurred AT ALL in a world where global warming did not exist. The studies suggested that the record-breaking global temperatures in 2016, an extreme heat wave in Asia and a patch of unusually warm water in the Alaskan Gulf were only possible because of human-caused climate change. Scientists say these are likely not the only events to occur strictly because of climate change. They're just the first to be discovered.
A November report from the Global Carbon Project found that carbon dioxide emissions are growing again after being flat for three years. The research, which was presented at the United Nations climate conference last month in Germany, projects that 2017 could see a 2 percent increase in the burning of fossil fuels. To rub salt into our collective wounds, we also saw super powers like the US led by President Trump backing out from the accord. As of to compensate our sagging morale, we also saw a hero emerge in Europe with French President French President Emmanuel Macron, pledging to fund climate research - a great source of hope for climate advocates like me.
With this level of hope, we will bid adieu to 2017 and greet 2018 with hope, optimism and prayers for the planet. May we see our planet with a smile on its face in the year ahead....