Thursday, 17 August 2017

Climate Change - "The climate has always changed .......what is all the fuss about?"

The climate has changed before.


When people say "It's changed before without people, so people can't be involved this time" ....think of forest fires.



Fires happened throughout time, does that mean people can't start fires?

Ice ages, warm times ... the geological record in the rocks shows many events.

Even so, the current changes are very unusual.





Graph based on a paper published in 2013

The recent rise in temperature is very fast.

What other kinds of changes are happening?


Geologists have compared the past with the present.


This report -
Climate Change Evidence: The Geological Society of London


explains what they have discovered.

This is based on part of that report:

"Before the current warming trend began, temperatures were declining.

This cooling took Earth’s climate into the ‘Little Ice Age’ (1450 – 1850). 

Calculations indicate that this period of cool conditions should continue for about another 1,000 years. 

Nevertheless, after 1900 the overall decline in temperature sharply reversed." 

So the Earth should be cooling.

There's lots of evidence for human involvement in these changes.  
Atmospheric CO2 is now around 400 parts per million (ppm).
It last reached similar levels during the Pliocene, 5.3-2.6 million years ago.
Outcrop view

In the middle Pliocene, the concentration of carbon dioxide in the air ranged from about 380 to 450 parts per million. 

During this period, the area around the North Pole was much warmer and wetter than it is now.

Summer temperatures in the Arctic were around 15 degrees C, which is about 8 degrees C warmer than they are now.
Global average temperatures were 2-3°C warmer than today.

Sea level rose by up to 20 metres in places.

What are the risks?
This source gives examples relating mainly to the USA ..........

but applicable more widely too.

For more interesting information, see -

Fact Sheets produced by 

Wednesday, 16 August 2017

Climate Change - Greenland

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.

Embedded image permalink

A survey of Greenland's glaciers has shown they are speeding up.

The speed has increased by about 30% in 10 years.

A new NASA project called Oceans Melting Greenland (OMG) will observe changing water temperatures on the continental shelf surrounding Greenland, and how marine glaciers react to the presence of warm, salty Atlantic water.

Updates about Greenland's ice sheet are regularly posted by the National Snow and Ice Data Center.

Tuesday, 15 August 2017

Climate Change - The End-Permian Mass Extinction

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.



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. 

A large amount of coal had been burned over a period of tens of thousands of years.
The coal was burned by the Siberian Traps volcanic activity.
The burning actually happened underground, with the carbon dioxide and ash mixing with magma.

This produced vast amounts of CO2 which warmed the Earth and changed the chemistry of the oceans.
The research team, led by Dr Matthew Clarkson from the University of Edinburgh, examined rocks in the United Arab Emirates. 
Siberian Traps
The rocks, which were on the ocean floor at the time, preserve a detailed record of changing oceanic conditions. 

The carbon was released at a similar rate to modern emissions. 
Matthew Clarkson image
Dr Clarkson says "Scientists have long suspected that an ocean acidification event occurred during the greatest mass extinction of all time, but direct evidence has been lacking until now.
"This is a worrying finding, considering that we can already see an increase in ocean acidity today that is the result of human carbon emissions."

Monday, 14 August 2017

Climate Change - El Nino

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 by an El Nino event ... but 2015 would have been the warmest year in the modern record even if there had been no El Nino.

Information about El Nino is provided in bulletins produced by the US National Weather Service and the Australian Bureau of Meteorology.

Sunday, 13 August 2017

Planet Earth - Doggerland

For many years, fishermen in the North Sea, between Britain and Denmark, have found fossil bones in their nets.



This fossil catch has yielded over 200 tons of fossil bones, and over 15,000 mammoth teeth.   

The bones include remains of mammoths, three different species of woolly rhinos, hippos, lionsbears, wild horsesbison, elk, reindeer, hyenas, wolves, and Sabre tooth cats of at least two species.   

They tell us about a whole community of animals.

Beneath the North Sea lies a lost landscape.

This land was as big as modern Britain - hills and valleys, rivers and forests, marsh and moor. 

Sometimes warm and marshy, and at other times a frozen tundra.

This has been named "Doggerland".



"Doggerland" is a name given to a vast lowland plain, with the northern coastline stretching from Shetland to Jutland. 

The Thames flowed into the Rhine, which turned south, and made the English Channel its estuary. 

The highest point was a hilly region where the Dogger sand-banks are today.

Saturday, 12 August 2017

Climate Change - A report on 2016 - yet another record-breaking year

The State of the Climate in 2016 report was released online on August 10th 2017 by the American Meteorological Society (AMS)


2016 was the warmest year in 137 years of record-keeping - the third year in a row of record-breaking temperatures.
The record resulted from the combined influence of long-term global warming and a strong El Niño early in the year.
Map of global surface temperatures in 2016
Global average sea level rose to a new record high in 2016.
Map of global sea level in 2016
A general increase in the water cycle (the process of evaporating water into air and condensing it as rain or snow), combined with the strong El Niño, enhanced the variability of precipitation around the world.
Map of global drought and moisture conditions in 2016

Friday, 11 August 2017

Climate Change - The Experts

In the latest survey by Dr James Powell, 69,402 out of 69,406 climate change researchers accept human activity is causing global warming.

What do scientists who research climate change say?

Professor Tim Palmer FRS, Royal Society Research Professor in Climate Physics, University of Oxford:



“The 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 Institute for Climate Change at Imperial College London:




“The evidence of changes in many different aspects of the climate system, from the ice sheets to the deep ocean, shows that climate change is happening.   
To reduce the serious risks posed by increasing changes in the climate, we need to redouble our efforts globally to limit carbon dioxide and other greenhouse gas emissions.”

The Royal Society has also published a "Short Guide to Climate Change" 

Another organisation offering an important document is the Geological Society of London.

                                 
The Geological Society of London say -

This rate of increase of CO2 is unprecedented.....

even in comparison with the massive injection of carbon into the atmosphere 55 million years ago that led to the major PETM warming event....

and is likely to lead to a similar rise in both temperature and sea level. 

From.....