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Showing posts from July, 2020

Climate Change - The UK in 2019

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The State of the UK Climate report, published by the Royal Meteorological Society  shows that UK temperatures in 2019 were 1.1° C above the 1961-1990 long-term average. Mike Kendon, lead author of the report, said: “Our report shows climate change is exerting an increasing impact on the UK. “This year was warmer than any other year in the UK between 1884 and 1990, and to find a year in the coldest 10 we have to go back to 1963.” Dr Mark McCarthy, from the Met Office, added it was a particularly wet year across parts of central and northern England. Rescuers used boats to reach people trapped in Rotherham as days of persistent rain led to almost 50 flood warnings across England in November 2019 He said: "It’s worth noting that since 2009 the UK has now had its wettest February, April, June, November and December on record – five out of 12 months." Graphic from UK Met Office.

Climate Change - Greenland

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The invention of the name " Greenland"  may mark the start of the advertising industry. The  Saga of the Greenlanders  tells how  Erik the Red , the Icelandic Viking who wanted to get people to join his planned settlement, called it Greenland because a pleasant name would attract more settlers: He called the land which he had found Greenland, because, quoth he, "people will be attracted thither, if the land has a good name."  The  ice sheet  on Greenland covers most of this huge island. Greenland is losing ice, and the mass of ice lost is measured by satellites called GRACE. A survey of Greenland's glaciers  has shown they are speeding up. The speed has increased by about 30% in 10 years. A paper published in June 2019  predicts that  Greenland will very likely become ice free within a millennium without substantial reductions in greenhouse gas emissions. A new NASA project called  Oceans Melting Greenland (OMG)   will observe changing water temper

Climate Change - The End-Permian Mass Extinction

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Five major  mass extinction  events are recorded in the rock record of the last 600 million years. The biggest extinction was at the end of the  Permian , around 252 million years ago. It is called the  End-Permian mass extinction. Only about 8% of species survived to live on in the Triassic Period. Field photograph of the Permian-Triassic boundary (PTB) section at Xiakou, Hubei Province,  South China. The event played out over 60,000 years. Acidification of the oceans  lasted for about 10,000 years. Two separate pulses of CO2 into the atmosphere - a "one-two punch" - may have been involved in the die-off, according to  new research. CO2 was released by massive volcanism from the  Siberian Traps , now represented as a large region of volcanic rock.  Researchers have found fly ash, one of the products of coal combustion, in rocks laid down just before this extinction event. A large amount of coal had been burned over a period of ten

Climate Change - El Nino

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El Niño  is an  oscillation of the ocean-atmosphere system in the tropical Pacific , and has important consequences for weather around the world. El Niño  happens every three to seven years. “El Niño” is Spanish for “The Little Boy”. Peruvian fishermen named the event many years ago. They noticed that every few years around Christmas, virtually no fish could be found in the unusually warm waters.  El Niño is marked by  unusually warm ocean temperatures  in the Equatorial Pacific. The opposite conditions are called  La Nina  (The Little Girl), characterized by  unusually cold ocean temperatures  in the Equatorial Pacific.  El Nino clearly affects global temperatures. One piece of evidence that world temperatures are rising is that every  La Nina  ‘year’ since 1998 was warmer than every  El Nino  ‘year’ before 1995:   As the Earth warms, each El Nino 'rides' on a higher base-line global temperature: The  record-breaking temperatures of 2015  were partly boosted b

Climate Change - The Experts

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What do scientists who research climate change say? Professor Tim Palmer FRS, Royal Society Research Professor in Climate Physics, University of Oxford: “T he threat of dangerous man-made changes to global climate is quite unequivocal.  It follows that if we want to reduce this threat, we must cut our emissions of greenhouse gases." Professor John Shepherd FRS, Ocean & Earth Science, University of Southampton: “The evidence is very clear that the world is warming, and that human activities are the main cause.  Natural changes and fluctuations do occur but they are relatively small." Professor Joanna Haigh CBE FRS, Professor of Atmospheric Physics, Imperial College London: “ The concentration of carbon dioxide in the Earth’s atmosphere now exceeds anything it has experienced in the past 3 million years and its continuing upward trend is almost certain to result in further global warming." Professor Sir Brian Hoskins FRS, Director of the Grantham

Climate Change - 1816 - The Year Without a Summer

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The climate can react to sudden shocks. The weather in  1816  was very strange.  Spring arrived, but then everything seemed to turn backward, as cold temperatures returned.  The sky seemed permanently overcast.  T he lack of sunlight became so  severe that farmers lost their crops. Food shortages were reported in Ireland, France, England, and the United States. 1816 became known as  "The Year without a Summer"  or "18-hundred-and-frozen-to-death". It was over 100 years before anyone understood the reason for this weather disaster. The eruption of an enormous volcano on a remote island in the Indian Ocean a year earlier had  thrown enormous amounts of volcanic ash  into the upper atmosphere. The dust from  Mount Tambora , which had erupted in early April 1815, had shrouded the globe.  With sunlight blocked, 1816 did not have a normal summer. In Switzerland, the dismal summer of 1816 led to

Climate Change - Ocean acidification - what does it mean?

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The phrase ' ocean acidification ' means that the  pH of seawater  is falling. The  pH scale  is used by scientists to describe  strength  of acids and alkalis.  Sea water  normally had a pH around 8.2  It has now reduced to 8.1, and will continue to reduce, as more CO 2  is added to the air by human activities. Some of the extra CO 2  in the air  dissolves  in the sea, and this affects sealife. Here is what one expert scientist has said about this - "A drop of 0.1-unit pH is equivalent to about a 26% increase in the ocean hydrogen ion concentration. "pH is likely to drop by 0.3-0.4 units by the end of the 21st century.   "This will increase ocean hydrogen ion concentration (or acidity) by 100-150% above what it was in pre-industrial times." Scott Doney, Senior Scientist, Woods Hole Oceanographic Institution, USA       Humanity's greenhouse gas emissions may be acidifying the oceans at a faster rate than at any time in the last 3

Climate Change - 2019 temperatures (and the most recent years)

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Berkeley Earth,  a non-profit research organization, has produced a report on global temperature changes based on data up to the end of 2019. The last 5 years stand out as a period of significant warmth  well above all previous years  since 1850. This reflects the long-term trend towards global warming. 2019 was the second warmest year on Earth, in records starting in 1850.  The global mean temperature in 2019 was lower than 2016, but warmer than every other year that has been directly measured. El Nino months are in red.  La Nina months in blue. Neutral months in grey. Both 2015 and 2016 were warmed by an extreme El Niño event that peaked in Nov/Dec of 2015 and was reported by NOAA as  essentially tied  for the strongest El Niño ever observed.  The exceptional El Niño boosted global mean temperatures in 2015 and 2016.  By contrast, 2019 began with a  weak El Niño event  and finished with neutral conditions. Global mean temperature in 2019 was estimated to be 1.28 °C (2.31

Climate Change - Coal and carbon dioxide

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Coal, oil and natural gas are  fossil fuels . When they are burned, they  change the Earth's atmosphere. How is that possible?       C oal  is a good example. Coal was formed  hundreds of millions of years ago . Geologists say that a three-metre (10-foot) coal seam took between  12,000 and 60,000 years  to form . Ancient trees and other plants lived, died and were fossilised. All those plants took  carbon dioxide  out of the atmosphere.  Some larger coal seams are, for example, 10 metres thick. They took around  40,000 years to form,  but have been mined and burned in a little over  100 years. The fastest rise of CO 2  in the air seen in   the ice core record (800,000 years)  is  20 ppm in 1000 years. The CO 2  level in the atmosphere is now rising at around  20 ppm per decade . The  carbon  joins up with  oxygen  when it burns. Each  carbon atom  joins with two  oxygen atoms  to make a  carbon dioxide molecule .  As a result,  oxygen concentrati

Climate Change - Carbon Sinks

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Carbon sinks  are natural systems that suck up and store  carbon dioxide  from the atmosphere. The main natural carbon sinks are  plants, the ocean and  soil.   Plants  grab carbon dioxide from the atmosphere to use in  photosynthesis ; some of this carbon is transferred to soil as plants die and decompose.  The  oceans  are a major carbon storage system for carbon dioxide.  Marine life also takes up the gas for photosynthesis, while some carbon dioxide simply dissolves in the seawater. 35 billion tonnes  of CO2 are produced each year by human activities. Currently, natural processes are absorbing about half of that. The remaining carbon dioxide is building up in the atmosphere.

Climate Change - Corals and Coral Bleaching

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Healthy  coral  can be very colourful. Some coral reefs have started to look rather different. This is called ' coral bleaching '. To understand this, we need to start by looking at corals. Corals are animals that make a framework around them  that looks like rock. Coral animals ( polyps ) have tiny  plants -  algae  - living in their tissues. The algae provide food to the corals, which they produce by  photosynthesis . Reef-building corals only live in a limited temperature range. Like porridge, they should be 'not too hot and not too cold'. Coral reefs  are concentrated in a band around the equator, between 30 ° N and 30 ° S latitude. Algae in corals need light Corals grow in warm, clear, shallow waters that receive plenty of light. Most corals grow in the warmest water they can stand (about 85° F or 29° C).  This means that slight increases in ocean temperature can harm corals. High sea temperature is the main reason for coral bleaching.

Russell Coope & the Discovery of Abrupt Climate Change

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Many people think climate change always happens slowly, but that is not the case......rather than hundreds, or thousands, of years, sometimes it can happen in decades. "Abrupt climate change"  was discovered by accident by Russell Coope (1930-2011), over 50 years ago. More recently he said: "We are  messing with the trigger  that causes climate change....the outcome is likely to be ferocious." In the 1950s, Russell Coope was a young geologist. He was studying layers of sediment formed during the  "Ice Ages" , a time geologists call the  Quaternary . He spotted something unusual in a quarry in the English Midlands.   This is his own description of what he found ... "I happened, entirely by accident, to visit a Quaternary gravel pit in which were exposed the spectacular bones of mammoth, woolly rhinoceros and bison.  Looking at their sediment matrix I was amazed to find enormous numbers of equally spectacular, if somewhat smaller, insect remai