ROCKY REX'S SCIENCE BITES

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, ...

Oil is a  fossil fuel . It was formed from chemicals from ancient living things. To make the chemicals in oil, the  temperatures  and  pressures  needed to be just right. The oil (and gas) will only stay in the reservoir if there are  suitable structures  in the rocks: The carbon compounds from the plants and animals have been trapped for hundreds of millions of years. They have been burned to make carbon dioxide in a very short time. The amount of carbon dioxide in the air has changed very quickly. Diagram of how oil is made Source:  Library and Archives Canada © Library and Archives Canada

What is the  worst-case scenario  for climate change? The geological record shows that when the atmosphere suddenly changes, there are big effects on living things. Every time in the geological past that gigatonnes of CO2 entered the atmosphere, the changes were very significant. The geological record contains examples of major temperature changes, associated with changes in atmospheric CO2. Events in which the temperature rose by several degrees in a geologically short time are called  hyperthermals. For example, the   PETM , around 56 million years ago: Matthew Huber at Purdue University calculated that warming slightly in excess of 10 degrees C—like that of the PETM and of pessimistic scenarios for future fossil-fuel burning—could render large portions of the planet uninhabitable for many creatures.  He has said : "There used to be subtropical forests near the poles 50 million years ago, and that doesn’t sound so bad. "But the fossil ...

Lots of people discuss ' climate change '. Some people confuse 'climate' with 'weather' - but i f 'climate' and 'weather' are the same, why would there be two words? Other people say "We call climate change 'winter' and 'summer'...."   What does the word ' climate ' mean? It normally means  the average of conditions over 30 years . Climate  normally means 'an average over 3 conventional decades'. A  conventional decade  is, for example, 2001-2010, or 1961-1970. So ..... 3 full, conventional decades......such as 1981 to 2010. For example .... rainfall in Ireland. And another example -  ' A verage temperature 1951-1980' The definition of 'climate' goes back at least 100 years. So if we are discussing  climate change , that is what 'climate' means. But in recent times, there has been a lot of variation in global temperatures. So it can ...

According to the  Royal Society ....... If human emissions of CO 2  stopped altogether... .... it would take thousands of years for atmospheric CO 2  to return to ‘pre-industrial’ levels. " The climatic impacts of releasing fossil fuel CO 2  to the atmosphere will last longer than Stonehenge, " says  University of Chicago oceanographer  David  Archer. "Longer than time capsules, longer than nuclear waste, far longer than the age of human civilization so far." Why is that? It takes a long time for deep oceans to bury the carbon dioxide in ocean sediments.  Lifee on the abyssal sea floor (depths ranging from 4000-6000 m) near the Hudson Canyon off the coast of New Jersey. Photo taken using the Deep Submersible Research Vessel (DSRV)  Alvin's camera system.  Image courtesy of Deep East 2001, NOAA/OER. Surface temperatures would stay high for at least a thousand years. Humans would face  a warmer planet due to past and curre...

The  Arctic   includes an  ocean covered by sea ice. Arctic sea ice  melts back in Summer, and then refreezes in Winter. The  area  of Arctic sea ice is largest in March each year, and at its lowest each September. It is reducing over time  - the graphs come from the US  National Snow and Ice Data Center. The NSIDC also publish this graph, which is normally updated every day. More graphs and other data are also available from the  Arctic Data Archive System , operated by the Japanese  Arctic Environmental Observation Center. New research   shows the decline in Arctic sea ice area since 1850: Research suggests   the remarkable decline of   Arctic sea ice over  the last century is far beyond anything seen for a long time.  

The  permafrost  of places like  Siberia  is not so permanently frozen any more. As it slowly melts, wonderful things are emerging, some frozen for tens of thousands of years. Baby mammoths  are sometimes found in an extraordinary state of preservation. "As the Earth warms, scientists worry that some of the carbon in permafrost could escape to the atmosphere as carbon dioxide or methane.  Increasing the amount of these gases in the atmosphere could make Earth's climate warm up even more." Arctic permafrost – ground that has been frozen for many thousands of years – is now thawing because of global climate change.  There are many effects of global warming, including melting permafrost, discussed in this useful document:  Physical effects of warming. The results of melting permafrost could be  disastrous and irreversible.