ROCKY REX'S SCIENCE BITES

Between about 20,000 and 5,000 years ago, Earth slowly changed from the frigid conditions of an  Ice Age , to the world on which our civilization has developed. As the  ice sheets  melted, colossal volumes of  water  flowed back into the oceans. The  pressures  acting on the Earth's crust changed as a result.  The  weight of ice  on the continents was reduced, and the rising seas put  extra water pressure  on the seafloors. In response, the  crust  moved up and bent, creating extra volcanic activity, increased seismic shocks and giant landslides. So if we continue to allow greenhouse gas emissions to rise unchecked, causing serious warming, will our planet's crust react once again? In Alaska, climate change has pushed temperatures up by more than 3 degrees Celsius in the last half century, and  glaciers  are melting at a staggering rate, some losing up to 1 kilometre in thickness in the last 10...

Hurricanes, cyclones, and typhoons are all the same weather phenomenon. We use those different names for these  tropical storms  in different places.  In the Atlantic and North-East Pacific, the term  “hurricane”  is used. So far,  Hurricane Patricia  is the strongest hurricane recorded at landfall.  Image of Hurricane Patricia tweeted by  astronaut Scott Kelly . In the North-West Pacific a tropical storm is called a  “typhoon” , and  “cyclones”  occur in the South Pacific and Indian Ocean. Three strong tropical storms  (Kilo ,  Ignacio , and  Jimen a) ,  formed in the Pacific in 2015. On Sunday 30th August, all of them were a category 4.  This was the first time the north-eastern Pacific had seen three category 4 hurricanes at the same time. Multiple cyclones in the Pacific Ocean in 2015 Tropical storms  can’t form outside the tropics - water temperatures are too cold. Sea surface...

Marlin  can hunt in water a half mile down, and sailfish often dive deep too. In more and more places around the world, ocean predators are sticking near the surface. Why? Warming temperatures are  sucking oxygen out of waters  even far out at sea, making enormous stretches of deep ocean hostile to marine life. Vast stretches of the ocean interior  suddenly lost oxygen  during the transition out of the last  glacial stage , between 17,000 and 10,000 years ago.  This event was the most recent example of large-scale global warming.

This graph shows how  carbon dioxide  has increased and decreased over hundreds of thousands of years. The low readings match with times called ' glacial stages '. During glacial stages,  ice  covered large areas of the Earth. The peaks in the graph show times when carbon dioxide was high, matching times called ' interglacial stages '. The most recent glacial stage occurred between about 115,000 and 11,500 years ago.   The  last interglacial period  occurred before it, from around 130,000 to 115,000 years ago. It's official international name is the  Eemian,  but it has other names in specific places. Climate information from that time is particularly useful. During that time,  temperatures  on earth were higher at the poles than they are now.  The  sea level  was between five and nine metres higher than current levels, because of the melting of ice in  Greenland  and  A...

July 2015 was the warmest month in the modern temperature record. The average temperature for July 2015 across global land and ocean surfaces was 1.46°F (0.81°C) above the 20 th  century average, according to the  United States National Oceanic and Atmospheric Administration. They say: "As July is  climatologically the warmest month for the year , this was also the all-time highest monthly temperature in the 1880–2015 record, at 16.61°C, surpassing the previous record set in 1998 by 0.08°C." The first 10 months of 2015  comprised the warmest such period on record across the world's land and ocean surfaces, at 0.86°C (1.55°F) above the 20 th  century average, surpassing the previous record of 2014 by 0.12°C (0.22°F).  

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 di...

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