ROCKY REX'S SCIENCE BITES

Farmers can put up with some bad weather, but  climate change  will make unusual events more likely. 20-30% of plant and animal species will be more likely to become extinct if the temperature rises by more than 1.5-2.5C. There will be big effects on farming from droughts and floods. The biggest effects will be seen first near the  Equator . Just  being near the Equator  makes it more difficult for countries to make economic progress. Hotter conditions affect how crops grow. Our agriculture is heavily reliant on  grasses  from the temperate regions. Corn, wheat, and rice  are all types of grass. The Tropics will expand as the world warms, so the world will find it harder to grow those important crops. People will  try to leave places  where they cannot produce enough food. Countries where  food prices  rise rapidly tend to become unstable, making  conflicts  more likely. Global w...

Climate change will affect people in many ways. Sea levels are rising more than twice as fast as the global average in the Sunderbans. The Sundarbans are  a low-lying delta region made up of 200 small islands in the Bay of Bengal. Around 13 million impoverished Indians and Bangladeshis live in t he Sundarbans.    Scientists predict much of the region could be underwater in 15 to 25 years, forcing the largest ever human migration in history. A 2013 study by the Zoological Society of London  found the Sundarbans coastline retreating at about 200 metres a year. Oceania is a region made up of thousands of  islands throughout the Central and South Pacific Ocean . It includes Australia, the smallest continent in terms of total land area. Many of the nations in Oceania are Small Island Developing States (SIDS). Many scientists say that Oceania is more vulnerable than most parts of the Earth to climate change, because of its climate and geography...

In 40 years, the distribution of rainfall in  Australia  has changed. Changes like this affect  water supply  to cities and to agriculture. Many parts of the world will see problems with water supply as climate change continues. Since the 1940s, farming on the southern  Great Plains  of the USA—Colorado, Kansas, Oklahoma and Texas—has relied on irrigation.  On the high plains of Texas, tens of thousands of wells pumping from the 10-million-year-old  Ogallala Aquifer  have reduced the water content by 50 percent.  Most of the  remaining underground water source will probably be useless  within about 30 years. Katharine Hayhoe , professor and director of the Climate Science Center at Texas Tech University in Lubbock, says big changes are on the way for agriculture on the Great Plains. "We're seeing major shifts in places and times we can plant, the types of crops we can grow and the pests and diseases we're dealing w...

Some people claim that someone decided that ' global warming ' should now be called ' climate change '.   It never happened. For example, Gilbert Plass published research in 1956 -  'The Carbon Dioxide  Theory of  Climatic Change'. The two terms mean different things, and both have been used for decades. The words  climate change  and  global warming  are often used interchangeably.  However, they do have slightly different meanings: Global Warming  has a very clear meaning. Global warming  refers to  increases in the Earth’s average temperature,  because of greenhouse gases building up in the atmosphere.  Global warming is a cause of climate change. Climate Change  is a broader term. Climate change  refers to changes (increases or decreases) to  long-term weather patterns , such as temperature, rainfall or snowfall. A warmer Earth, from global warming, will lead to changes includ...

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 . Note that in the "Years before present" scale, zero = 1950 AD 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 ...

W hy can’t recent  climate change  just be an effect of 'natural causes'? There have been climate changes in the past 2000 years. People talk about times called the  Medieval Warm Period  and  the  Little Ice Age . Careful research  has shown that the current temperature rise is much bigger than the Medieval Warm Period.  Climate scientists have discovered that the  Medieval Warm Period  had a number of causes. The Sun was more active, and volcanic activity was low, which both increase warming.  Other evidence suggests ocean currents changed, bringing warmer seawater into the North Atlantic. When these factors changed, the Earth resumed cooling, creating the  Little Ice Age. The  I ndustrial Revolution , when  coal burning  began on a large scale, started the recent rise in temperatures, reversing the cooling trend.

Some key events in the discovery of climate change 1800-1870  Level of carbon dioxide gas (CO 2 ) in the atmosphere, as later measured in  ancient ice , was about 290 ppm (parts per million). Global temperature for 1850-1870 was about 13.6°C. 1824 Jean-Baptiste Joseph F ourier  calculated that the Earth would be far colder if it lacked an atmosphere.  1859 John Tyndall  discovered that some gases block infrared radiation.  He suggested that  changes in the concentration of the gases  could bring  climate change . 1896  Arrhenius  published first calculation of global warming from human emissions of CO 2 . 1930s  Milutin Milankovitch  proposed orbital changes as the cause of ice ages.  1938  Guy Callendar  showed that  global warming was underwa y,  reviving interest in the question.  1950s  By accident,  Russell Coope  discover...

"Reaching the 400 ppm mark  should be a reminder for us that carbon dioxide levels have been shooting up at an alarming rate in the recent past due to human activity.  "Levels that high have only been reached during the Pliocene era, when temperatures and sea level were higher.  "However, Earth's climate had never had to deal with such a drastic change as the current increase, which is, therefore, likely to have unexpected implications for our environment." – Dr. Carmen Boening Scientist, Climate Physics Group – NASA Jet Propulsion Laboratory Scientists know that recent climate change is caused by human activities.   The speed of the current climate change is faster than most  past warming events, making it more difficult for human societies and the natural world to adapt.  The key ideas are explained in a publication called - Climate Change: Evidence and Causes It was put together by the Royal Society  and the National Aca...

Each time there are  extreme weather events , people debate "Is there a link to climate change?" It might be hard to prove in many cases. Some recent events, however, are extraordinary. The phrase 'weather on steroids' has been used to describe these events. In 2015,  Boston ’s month of snow was a  1-in-26,315 year occurrence. Yet   the amount of wintertime cold air  circulating around the Northern Hemisphere is shrinking to record low levels. Researchers are looking at possible links to climate change in some cases of extreme weather. One scientist investigating this problem is  Professor Jennifer Francis. Prof Francis is interested in how  t he odd behaviour of the jet streams may link to the warming of the polar areas. For example, in  2010  ...... There were some very unusual weather events in 2010, which may be a warning of future effects of climate change. Each time there are  extreme w...

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 100 years.  The reduced weight on the crus...