Climate change is the biggest threat to the survival of planet earth we have ever encountered. It is a large-scale, long-term shift in the planet’s weather patterns and average temperatures. It is important we take heed. There must be no denying it.
Since the last ice age about 11,000 years ago, the Earth’s climate has been relatively stable, with an average global temperature of about 14 °C. However, we know that global temperatures have risen significantly over the 20th and 21st centuries, primarily as a result of a rise in atmospheric carbon dioxide (CO2).
Since the Industrial Revolution, CO2 in the atmosphere has increased by over 40% to levels that have never been seen. This has caused warming throughout the climate system, and many indicators prove that our climate is changing.
Global average surface temperature has increased by about 1 °C since the 1850s. Each of the last three decades has been successively warmer than any other preceding decade and 16 of the 17 warmest years on record have occurred since the year 2001.
Rainfall has increased in the mid-latitudes of the northern hemisphere since the beginning of the 20th century. There are also changes between seasons in different regions. For example, the UK’s summer rainfall is decreasing on average, while winter rainfall is increasing. There is also evidence that heavy rainfall events have become more intensive, especially over North America. We are seeing flooding on unprecedented levels.
Changes in nature
Changes in the seasons (such as the UK spring starting earlier, autumn starting later) are bringing changes in the behaviour of species, for example, butterflies appearing earlier in the year and birds shifting their migration patterns.
Sea level rises
Since 1900, global average sea level has risen by more than 20 cm. The rate of sea-level rise has increased in recent decades from around 1.7 mm per year over the last century, to 3.3 mm per year since the early 1990s.
Glaciers all over the world, in the Alps, Rockies, Andes, Himalayas, Africa and Alaska are melting and the rate of shrinkage has increased in recent decades.
Arctic sea-ice has been declining since the late 1970s, reducing in extent by about 4%, or 0.6 million square kilometres per decade. The summer minimum Arctic sea ice extent has decreased by 13.3% per decade since 1979. At the same time Antarctic sea-ice has been more stable, though most areas have been at very low levels since autumn 2016.
The Greenland and Antarctic ice sheets, which between them store the majority of the world’s fresh water, are both shrinking at an accelerating rate.
The United Nations has recently held talks about climate change again in Poland. This conference is the most critical on climate change since the 2015 Paris agreement. At the opening ceremony UN Secretary-General, said climate change was already “a matter of life and death” for many countries. He explained that many of the countries, most responsible for climate change were still behind in their responsibilities, primary USA and China.
Speaking at the conference in Poland, Sir David Attenborough said: “Right now, we are facing a man-made disaster of global scale. Our greatest threat in thousands of years. Climate Change. If we don’t take action, the collapse of our civilisations and the extinction of much of the natural world is on the horizon.”
Although the USA has withdrawn from the Paris agreement, it cannot leave until 2020, so its negotiators have been taking part in meetings and have not obstructed the process. However, given the President’s well-known support for coal, in spite of the overwhelming evidence it has been anticipated that the White House will again organise a side event promoting fossil fuels.
The world needs to work together to come to understand climate change. Bringing our personal opinions into whether climate change exists is damming. just because certain countries may not believe it, doesn’t mean it’s not happening.
The reality is, it’s happening, and we must act now. To deny that means future generations and animals will struggle to survive.