Evidence builds on climate change
(WHAM) - The State of the Climate 2017 has been published, the 28th annual summary for the planet and is based on contributions from more than 450 scientists.
From the American Meteorological Society, this statement provides an update on global climate indicators, significant weather events including data collected from land, water, ice, and even space. Some of the climate indicators include greenhouse gases, temperature, precipitation, sea level, sea ice extent, glacier mass, snow cover, and tropical cyclones.
Some of the headlines from this report include:
- All the dominant greenhouse gases released into the Earth’s atmosphere – carbon dioxide, methane and nitrous oxide have increased to new record highs.
- At the Earth’s surface, average carbon dioxide increased to 405 ppm which is highest in the modern atmospheric measurement record. It is also the highest in ice core records dating back as far as 800,000 years. The global growth rate of carbon dioxide has nearly quadrupled since the early 1960s.
- Global surface temperatures for the year were 0.38 -0.48°C above the long-term average. This may not seem like a lot, but 2017 was the warmest annual global temperature since records began in the mid to late 1800s.
- During this record, the four warmest years have occurred since 2014.
- In the Arctic (above 60° north latitude), average air temperature over land continued to increase at a rate twice the rate of the rest of the world.
- Arctic sea ice measured by satellite was 8% below the long-term average, making it the record-lowest maximum in the 38-year period of record.
- However, the Greenland ice sheet rebounded from the dramatically low mass in 2016 and was the lowest melt area since 1996.
- In Antarctica sea ice extent remained low for 2017 and well below the long-term average (1981-2010).
- The U.S. was impacted by 16 weather and climate events that each caused over $1 billion in damages. Since 1980, last year was tied with 2011 for the greatest number of billion-dollar disasters.
This is just a few samples of this extensive summary and if you wish to get the full report you can visit the site here.
History shows the climate is always changing, however many of the observations are beyond what we call a “natural variability”. There is no doubt that the Earth’s interconnected atmospheric, oceanic and terrestrial system is complicated and will require more study. But the atmosphere has shown dramatic changes during the past century and this is based on hundreds of peer-reviewed scientific papers. It is clear these changes are due to human induced activities which include increases in carbon dioxide, methane and nitrous oxide.
I once heard the analogy that if the Earth were to be considered the size of a beach ball, the atmosphere surrounding the earth would then be equivalent to the thickness of an envelope. If you consider the amount of pollutants that we have created since the beginning of the industrial revolution, and that the Earth’s atmosphere is a finite resource, how can it be that we have not had some kind accelerated change in the climate?