Friday, 30 September 2016

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.....

Climate Change: Evidence from the Geological Record


Thursday, 29 September 2016

Planet Earth - 1816 - The Year Without a Summer

Climate reacts to sudden shocks.

The weather in 1816 was unprecedented. 

Spring arrived but then everything seemed to turn backward, as cold temperatures returned. 

The sky seemed permanently overcast. 


The lack of sunlight became so severe that farmers lost their crops.

Food shortages were reported in Ireland, France, England, and the United States.

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 the writing of a famous story. 

A group of writers, including Lord Byron, Percy Bysshe Shelley, and his future wife Mary, challenged each other to write dark tales inspired by the gloomy and chilly weather.

During the miserable weather Mary Shelley wrote her classic novel Frankenstein.

This event was not unique.

A new study has found that 15 of the 16 coldest summers recorded between 500 B.C. and A.D. 1,000 followed large volcanic eruptions.

Wednesday, 28 September 2016

Climate Change - Glacial archaeology

Norway is dotted with small glaciers, and 'permanent' snow patches .

Around 7,000 years ago (5000 BC) the Earth was enjoying a warm climate:



Then it cooled, allowing those icy areas to form.



Now those glaciers and patches of perennial ice in the high mountains of Southern Norway have started to melt again, as the Earth is warming. 

They contain all sorts of archaeological treasures.

Anything from ancient shoes to 5000-year-old arrowheads. 

As a result a new kind of archaeology has begun - Glacial archaeology.

6_norways-oldest-shoe

In 2006, an amateur archaeologist came across an amazingly well-preserved ancient leather shoe in the Lendbreen ice patch in Norway. 

When the shoe was examined and tested, archaeologists discovered the shoe was over 3,000 years old, and dated from the Bronze Age.


"Actually we should be slowly approaching a new ice age. 
But in the past 20 years we have witnessed artefacts turning up in summer from increasingly deeper layers of the glaciers." says Lars Pilø.
Lars does fieldwork in glaciers and ice patches, finding things discarded or lost by people long ago.

Glacial archaeology is becoming a fascinating new field of research.

Tuesday, 27 September 2016

Interesting Scientists - Fred Shotton and the D-Day Beaches

In June 1944, a vast army of troops from Britain, the USA, Canada, France and other countries landed on beaches in northern France to begin the push to remove Adolf Hitler's forces from France.

There were many secret preparations but one vital part of the story was the Shotton Map....



Starting in the October of 1943, a team including geologist Fred Shotton worked to produce detailed geological maps of all the beaches in the area, to help choose the invasion beaches.

Shotton took part in secret flights to observe the beaches, using a special glass-bottomed aircraft.

Special forces teams were sent on very dangerous missions to swim ashore at night to collect samples of sand from the beaches, so that they could be analysed by the geologists.



Fred Shotton became Professor of Geology at the University of Birmingham in central England.

He became an expert in the study of the 'Ice Age'.



Monday, 26 September 2016

Climate Change - Ocean acidification - what does it mean?

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 CO2 is added to the air by human activities.



Some of the extra COin 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."



Humanity's greenhouse gas emissions may be acidifying the oceans at a faster rate than at any time in the last 300 million years. 

With ocean acidification, corals cannot absorb the calcium carbonate they need to maintain their skeletons.

The stony skeletons that support corals and reefs will dissolve.


Picture A shows healthy coral.     Picture B shows dead and dying coral.
A healthy coral reef with living Acropora palmata and good water quality and a degraded coral reef with dead A. palmata and poor water quality.  

The U.S. Geological Survey (USGS) is conducting research on ocean acidification in the Arctic, Gulf of Mexico and Florida estuaries, and the Caribbean and Pacific.

Sunday, 25 September 2016

Climate Change - What's going on with the Gulf Stream?

The Gulf Stream transports vast amounts of heat north, from the equator to the pole, passing off the East Coast of the U.S. and into the North Atlantic.



The Northern Hemisphere winter of 2014-15 was the warmest on record globally, according to the National Oceanic and Atmospheric Administration. 

But one area of the North Atlantic was the coldest on record... shown in blue on this map.Land and Ocean Temperatures

This cold pool may be an indicator of a dramatic slowdown in the Gulf Stream.

A slowdown like this in the current has not happened for a very long time, perhaps as long as 1,000 years. 

It is possibly related to the melting of the Greenland ice sheet. 

The freshwater from the ice sheet is lighter than heavier, salty water that usually occupies that area. 

It tends to sit on top of the water, interfering with the sinking of dense, cold and salt-rich water.



The Gulf Stream transports more water than "all the world's rivers combined," according to the National Oceanic and Atmospheric Administration.

A rapid slowdown in the current would increase the rate of sea level rise along the Mid-Atlantic and North-east coasts of the U.S. 

It could also bring much cooler conditions to parts of northern Europe.

This is still a matter needing more research.

Saturday, 24 September 2016

Interesting Scientists - Professor Carolyn Porco - Saturn's greatest fan



Carolyn Porco's career has involved studying the results of space missions to the outer planets.

Starting with the Voyager probes in the 1980s, she became head of the Imaging Team for the Cassini Saturn mission, and part of the team for the New Horizons probe to Pluto.


In this video, Professor Porco explains why she can't get enough of Saturn.

Friday, 23 September 2016

Climate Change - 2015 - Warmest Year in Modern Record

The year 2015 ranked as Earth’s warmest year since records began in 1880.

This is reported by scientists from NASA and the National Oceanic and Atmospheric Administration. 


The average surface temperature has risen about 1.0 degree Celsius since the late-19th century.

Fig A2


Globally-averaged temperatures in 2015 beat the previous record set in 2014 by 0.13 degrees Celsius

NASA analysis estimates 2015 was the warmest year with 94% certainty.




2015 was the first time the global average temperature was 1 degree Celsius or more above the 1880-1899 average.

Global annual average temperature relative to 1961-1990 based on the three major global temperature datasets (HadCrut4, NASA GisTEMP and NOAA). 


 Source: World Meteorological Oroganisation

9 of the 10 warmest years in the record have occurred in the 21st century.

From earlier years, only 1998, affected by a strong El Nino event, makes fifth place.

Global mean monthly surface temperature anomalies show the record warmth of 2015-2016 in a graphic produced by Columbia University......

Thursday, 22 September 2016

Autumn Equinox in the Northern Hemisphere

Every place on earth experiences 12 hours of daylight twice a year, around the Spring and Autumn Equinox.

At the Equinoxes, the Sun rises almost exactly in the east, travels through the sky for 12 hours, and sets almost exactly in the west.



The September equinox marks the moment the Sun appears to cross the celestial equator – the imaginary line in the sky above the Earth’s equator – from north to south. 

After the September equinox, northern days continue to shorten until the December solstice.

Wednesday, 21 September 2016

Climate Change - Global Temperatures for August 2016

According to NOAA, August 2016 was the warmest August in the 137-year period of record.

This is the 16th consecutive record-breaking month. 


June, July, and August are the 3 months of meteorological summer in the northern hemisphere, and meteorological winter in the southern hemisphere.

In 2016, the June–August seasonal global land and ocean temperature was 0.89°C above the 20th century average of 15.6°C

This was the highest temperature departure from average for June–August in the 1880–2016 record, passing the previous record set in 2015 by 0.04°C.


Tuesday, 20 September 2016

Climate Change - Coal and carbon dioxide

Coal, oil and natural gas are fossil fuels.

When they are burned, they change the Earth's atmosphere.

How is that possible?      Coal 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 CO2 in the air seen in the ice core record (800,000 years) is 20 ppm in 1000 years.

The CO2 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 concentration in the air is slowly reducing.

Data recorded at Cape Grim Station, Tasmania.

No need to panic, however, as the reduction is around 2ppm per year.

The atmosphere contains 210,000 parts per million of oxygen, so the reduction in oxygen has little direct impact.

It does, however, confirm that the extra CO2 is being made by burning of materials containing carbon, which combines with atmospheric oxygen.

Monday, 19 September 2016

Climate Change - Carbon Sinks

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.

The figure of 33.4 billion metric tonnes of carbon dioxide is for 2010.  

The remaining carbon dioxide is building up in the atmosphere.

 Atmospheric CO2 data and trend

Sunday, 18 September 2016

Climate Change - Corals and Coral Bleaching

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.

Saturday, 17 September 2016

Climate Change - Russell Coope & the Discovery of Abrupt Climate Change

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 remains. 

I was hooked instantly! 

Particularly exciting to me was the fact that these insect fossils showed that Quaternary climates had changed abruptly. 

Thus, at times, fully glacial climates gave place to temperate interglacial conditions within the span of one human lifetime."


A well-developed sequence of ice age deposits at Bridgwalton Quarry near Bridgnorth, Shropshire. (Photo: Dave Evans).

This was the first discovery of evidence that the climate can change really quickly.

His discovery was later confirmed by evidence from ice cores from the Greenland ice sheet.

So how does Russell Coope's method work?

Different beetles prefer different temperatures.

By identifying the beetles in layers of sand or gravel, Coope could tell what climate existed in that place, and how it changed.

Experts still use Russell Coope's method.

This fossilised beetle is well preserved.
Fossilised_diving_beetle.jpg

Scientists often identify the fossil beetles from fragments.

This particular fossil is of a diving beetle found in the La Brea Tar Pits in California.

A recent research project links some of the abrupt climate change events in the last glacial stage to changes in ocean circulation.
“We know from ice cores in Greenland that large climate oscillations occurred during this time,” lead study author Gene Henry told Gizmodo. “We wanted to see if those climate oscillations had an imprint in circulation patterns.” 

Friday, 16 September 2016

Climate Change - Is the Sun causing Global Warming? Or about to cause Global Cooling?

It is often claimed that the Sun is causing global climate change.

The Sun is the source of the heat on the Earth, but it has not suddenly become more active recently.

The Sun may be going into a phase of lower activity - but that will not reverse global warming.

When the Sun's energy arrives at the Earth, it travels through the air.

Some is reflected back to space, but some hits the Earth and warms it.

The warm Earth gives off infrared radiation with various wavelengths.  


Some of those waves can pass back out of the air to space, but some are absorbed by certain gases in the air.


If there are more of those gases, less heat escapes into space, so the Earth warms.

In the graph below, from the Stanford Solar Center, carbon dioxide data comes from the Law Dome ice core in Antarctica, and from the observatory on Mauna Loa in Hawaii.


There is no doubt why the Earth is warming.

A new study says that even if the Sun's activity did drop off for a while, it wouldn't have much impact on rising global temperatures. 

It could mean a higher chance of some chilly winters in Europe and the US, but the researchers say:

There is now too much carbon dioxide in the air for there to be a repeat of the 'Little Ice Age'.


In fact, it is very likely that human activity has finally broken the cycle of glacial and interglacial stages.

Thursday, 15 September 2016

Climate Change - Floods more likely, and more damaging

Heavy rainstorms caused devastating flooding across a 12-county region of West Virginia in late June 2016.

Events like this are almost certainly made more frequent, and more intense, by global warming. 


A map from the National Weather Service shows the intensity of the rains that brought floods to the region.
Climate scientists from around the USA said that the overwhelming scientific evidence shows that the warming of the planet’s atmosphere is increasing the occurrence of, and the seriousness of, heavy rains.

Warmer air holds more water, leading to stronger and more frequent heavy precipitation events. 

This is confirmed by research done by a team of scientists of the Potsdam Institute for Climate Impact Research.


They find the worldwide increase to be consistent with rising global temperatures, caused by greenhouse-gas emissions from burning fossil fuels. 

Short-term torrential rains can lead to high-impact floodings.