Thursday, May 28, 2015

Final Canada Blog

Canada is a country that experiences virtually every type of natural hazard we know of.  From Hurricanes to Tornadoes, Volcanoes to Earthquakes, forest fires to landslides, Canada experiences all that Mother Nature has to offer.  However, not all regions of Canada experience each of these disasters.  Many of these hazards only occur in small regions of Canada.  Others occur very infrequently or in such remote areas that they do not impact the general population of Canada.  However there are two hazards that are widespread throughout Canada and these hazards are also directly related to one another.  Each year, the hazards that cause the most destruction and expense are Landslides and Severe Weather.
Canada experiences precipitation in all forms, rain, sleet, hail, snow, and ice.  Due to the warmth of the Pacific Ocean, the western coast of Canada receives very little snow, but can receive over 100 inches of rain per year.  Other regions on the Atlantic coast receive rain mixed with severe incoming wind in hurricane or cyclone from.  Snowfall generally increases when traveling west from the Atlantic, with the Rocky Mountains receiving an annual 240 inches of snow.  This combination of heavy wind, rain, and snow in such a cold climate can cause damage to power lines, roads, trains, and buildings.  After the initial impact of the rain and snow and as the ice and snow begins to melt, our second natural hazard begins to occur.
Landslides are very frequent in Canada, due to several geographical factors.  The terrain of Canada is very mountainous and unstable.  This can cause debris and loose rock to fall, even without the outside influence of rain or water.  The heavy rain and snow Canada gets each year also leads to additional landslides.  During or following heavy rainstorms, landslides often form due to the force at which the rain hits or washes down a mountainside.  This flowing water can pick up rocks, mud, and other debris, gaining speed as it descends down a slope.     
Snow and freezing conditions only amplify the impact of landslides.  The snow itself can often add to the weight on loose soil, thus causing the initial slide.  Other times, the snow can be piled so high, a small amount of melt to the bottom layer of snow can lead to an Avalanche.  These landslides of snow can reach up to 280/mph and weigh up to 100,000 tons.  Sometimes these are triggered skiers, and each year there are stories about adventurers who do not survive their fall. 
Where we truly see how the severe weather can lead to landslides is the impact of ice.  Rainwater can become trapped in the small cracks between rocks on the large mountainsides of the Canadian wilderness.  Due to cold temperatures, this water will then freeze inside the rocks, expanding and increasing the size of the cracks.  When the ice melts, the water is released, and the structure of the rocks has been weakened.  Over time, this can lead to massive landslides containing tons of rock. 
The most advanced technology is being employed in order to monitor the movement of entire mountains by taking frequent satiate images to check for any differences.  In addition to increasing the range of this photo monitoring program, I would also monitor seismic activity for any warning signs of strong activity that could trigger a slide.  While there is little that can be done about weather, implementing stronger infrastructure for at risk areas would help reduce the impact of severe weather.  Identifying at risk locations and taking necessary precautions to reinforce structures and roads would also decrease damage caused by weather.  Both events need to be announced to the public as soon as possible, and evacuation of high risk areas would also reduce loss of life. 
There are many regions of Canada that could be identified as high risk.  Personally, I see the most at risk areas of Canada also to be the most remote.  Areas with low population often are less prepared to endure loss of power, roads, or water.  The Northeast, specifically Newfoundland, is sparsely populated, and experiences some of the most severe weather in Canada.  Other places such as Yukon and Northwest Territory would be at risk for landslides due to their rocky terrain.
If I was to build a house in Canada, I would choose to build it in Vancouver, British Columbia.  Just over 30 miles north of Washington, Vancouver is a city with virtually the same hazard risks as here in California, with a lot more rain.  This is a city that has plenty of resources, and less risk of landslides and forest fires than a more mountainous, remote region of Canada.  There is always the chance of a major earthquake, volcano, or tsunami, caused by the three tectonic plates along the Pacific coast.  However the risks of tornadoes, hurricanes, and landslides decreases greatly due to the climate of the Pacific as opposed to the east coast.  Personally, I am more comfortable with rare chance of an earthquake here on the Pacific coast, than the annual hurricane or blizzard experienced by the Atlantic coast.    







http://enr.construction.com/news/environment/archives/050614.asp

http://www.redcross.ca/what-we-do/emergencies-and-disasters-in-canada/for-home-and-family/make-a-plan/planning-for-landslides

https://www.nrcan.gc.ca/hazards/landslides


Sunday, May 3, 2015

Coastal Hazards in Canada

Canada has the longest ocean coastline in the world, and experiences a great amount of erosion.  While most of this coastline erodes at a moderate rate of less than 3 feet per year, parts of the Atlantic coastline experience up to 30 feet per year.  Some islands off the coast of Nova Scotia have incurred so much erosion, that the islands have now disappeared into the ocean.  Our textbook estimates that approx. 1 billion dollars are spent each year to control the erosion on the coast line. 

The eastern Atlantic coast of Canada’s shorelines is on a relatively inactive section of coast, of its distance from the convergent plate boundaries.  This leads to barrier islands and sandy beaches.  The western coast however is located near several active plate boundaries, which creates a very rocky mountainous coastline.  This coastline is also influenced by thick layers of ice, and movement of glaciers. 

The coastal region of Canada has an extreme rise between low and high tides.  This will produce “flood tides” that can rush in very quickly.  With a tidal range of 50 feet, these tides can come in as quickly as 3 feet every 23 min.  This quick change in tide level can be very dangerous for those who are not prepared for it.  This can lead to rip currents, and can catch even the most experienced swimmers in a very strong current.  In the event of a rip current, remaining calm and swimming parallel to the shore is the best way to get out of the current.   Attempting to swim directly at the current is generally unsuccessful, so swimming laterally to find a break in the strong current to swim back to shore  is the best way to avoid being swept further.



Information taken from Chapter 11 of our textbook, as well as:

http://www.tourismpei.com/beach-safety
https://www.nrcan.gc.ca/earth-sciences/science/water/marine-coastal-processes/10896




Saturday, April 25, 2015

Tornadoes in Canada

The pattern of tornadoes in Canada is very similar to here in the United States.  The central plains region in the US is nicknamed “Tornado Alley”, specifically from North Dakota to Kansas.  Manitoba and Saskatchewan lie directly above this region, and experience many tornadoes each year.  Saskatchewan can experience up to 18 tornadoes per year.  The most devastating tornado in the history of Canada occurred in 1912, in Regina, Saskatchewan.  It caused 28 deaths, hundreds of injuries, and over 400 buildings destroyed. 




Canada is vulnerable to many types of extreme weather.  Each year Canada is hit with blizzards, ice storms, hurricanes, heat waves and tropical storms.  Environment Canada is the agency responsible for issuing weather alerts.  Environment Canada is responsible for warning the public when conditions exist that may produce tornadoes or other extreme weather. Using radio, television, newspapers, its internet site, and weather phone lines, Environment Canada provides information regarding at risk area and evacuation locations.  There is also a program called “Weather Watchers,” a group of volunteer weather enthusiasts who monitor the skies for any extreme weather on the horizon.  Environment Canada employs 31 weather satellites, which cover areas prone to thunderstorms and severe weather conditions, as well as where 98% of the population is located.  Most regions of Canada advise to seek the shelter of a sturdy desk in the event of a tornado.  Half of the deaths from tornadoes occur from mobile homes being hit, due to the lack of foundation.  Exiting the mobile home and finding shelter in a ditch away from any possible debris.  





http://www.cbc.ca/news/canada/saskatchewan/top-10-deadliest-tornadoes-in-canadian-history-1.1267514

Saturday, April 18, 2015

Sinkholes in Canada

Sinkholes in Canada are actually a very common occurrence.  Sinkholes are common where the rock below the land surface is limestone, carbonate rock, salt beds, or rocks that can naturally be dissolved by the ground water circulating through them.  While many sinkholes are caused naturally by erosion and landslides under the surface of the earth, the sinkholes in Canada are in many cases man made.  Most sinkholes in Canada form under roads, due to the rupture or cracking of water and sewage lines underneath the roads.  The harsh winter and constant freezing and defrosting of these water systems puts a great amount of stress on the pipes below the roads.  Even a small leak can cause water to gradually seep into the soil under the roads, which will compromise the ability of the soil to support the surface above.  Over time, this can cause serious damage to the pipes and roads.  In some cases, when the pipes burst, the volume of water released into the earth can create sudden sinkholes with little or no warning signs.  

Certain areas of Canada are more prone to sinkholes do to a surface or subsurface layer of soft silt, leftover from the latest ice age.  This soft soil can cause risks of subsidence, especially near train tracks in remote areas.  Due to the large amount of snow melt each year, the runoff can cause the silt to soften and erode.  If the wrong structure is built on top of this silt, the structure can be destroyed.  This issue has been addressed, and efforts are being made to use higher quality materials in the construction of roads and water lines.  Many of the older, existing roads were built with a softer clay like soil beneath them.  Officials have worked to identify current risks for sinkholes, and are attempting to reinforce these areas.  This can prove to be difficult, as it would cause road closures and is an expensive process.  





http://www.canadianunderwriter.ca/news/hole-picture/1002925051/?&er=NA
http://globalnews.ca/news/401401/a-list-of-the-worst-sinkholes-in-canada-and-around-the-world/
http://www.cbc.ca/news/canada/why-the-ground-suddenly-gives-way-1.907424


Friday, April 10, 2015

Canada Landslides

Each year, there are thousands of landslides throughout Canada. The combination of steep mountains and melting ice flows makes Canada particularly vulnerable to landslides.  Each winter, when the frozen ice covering the mountains melts, it can cause the rocks to release from the mountain.  There are several strategies that are used to prevent the damage.

One interesting strategy that is being used in Canada is the use of satellite photo monitoring in high risk areas.  For example at Turtle Mountain, the satellite compares the position of  rock movement over a period of time to ensure the risk of landslides has not increased.  The distance is tracked over a period of about 24 days, and can detect movement of as little as 5 millimeters.  This information can be vital for preparing for a flow.

Other tactics used involve government planning to alert citizens of pending disaster.  Promoting people in high risk areas to take extra precautions such as evacuation plans, staying away from power lines, and understating that the grounds may be unstable for several days following an event.    


 

http://enr.construction.com/news/environment/archives/050614.asp

http://www.redcross.ca/what-we-do/emergencies-and-disasters-in-canada/for-home-and-family/make-a-plan/planning-for-landslides

https://www.nrcan.gc.ca/hazards/landslides

Friday, March 13, 2015

Tsunamis In Canada


The British Columbia coast is the only part of Canada that is at serious risk of experiencing a Tsunami.  Located on the Pacific Coast, between Washington and Alaska, British Columbia does have measures in place in the event of a tsunami.  BC uses a system of Watch, Advisory, and Warning.

Tsunami watch would be triggered by seismic activity occurring.  In the evening of seismic activity, local communities are notified they may be in danger of a Tsunami.  This is the notification that communities should start preparing, and they should implement their emergency plans.  Evacuation is not necessary at this point, but people should start to prepare for that possibility.

Tsunami Advisory are issued when seismic activity has created currents and conditions that could impact coastal areas.  While this does not pose a significant threat to lives and structures, the conditions could become dangerous.  At this point, harbors, marinas, and beaches should be evacuated, and people should avoid the coast.

Tsunami Warnings are issues when there is impending danger to the coast, as well as communities nearby.  All public evacuation plans should be implemented, and all coastal areas must be evacuated.  Coastal roads will be closed, and beach access will be restricted to emergency vehicles.

The threat of tsunamis is always present on the western coast of Canada, due to the 3 intersecting faults.  Currently, the tsunami warning system in BC is managed by the United States Department of Commerce.  British Columbia is included in the National Oceanic and Atmospheric Administration which is detects tsunamis and provides notification to all countries along the Pacific Ocean.  The Emergency Management British Columbia is in charge of receiving these alerts, and informing those communities at risk.



http://www.embc.gov.bc.ca/em/hazard_preparedness/Tsunami_Brochure/Prepare_for_Tsunami.html

http://www.canadiangeographic.ca/tsunami/tsunamis_canada.asp

Friday, March 6, 2015

Volcanic Activity in Canada

There has only been one documented volcanic eruption in the late 1700's, however there are many dormant volcanoes along the western coast of Canada.  The Tseax Cone Volcano occurred about 1775, and was responsible for approximately 2,000 deaths.  The lava destroyed several villages and created toxic gas around the area.  Lava flows engulfed the Nass river, forever changing the landscape.  

Currently, there are six volcanoes along the convergent plate boundary that separates the Juan de Fuca and North American plates.  While this area is considered to be in the “Ring of Fire” that is notorious for volcanic activity, these major events have occurred in Washington and Alaska.  The 1980 Mt. St. Hellens eruption occurred just 400 km from the US Canada border.  Mt. Baker, which is just 40 km from the US/Canada border, would be the biggest volcanic risk to the Canadian people in the province of British Columbia. 


Mt. Baker experienced a minor eruption in 1870, and steam can be seen coming from the top peak on a cold day.  Although this does not indicate a pending eruption, this does illustrate that Mt. Baker could erupt someday.  While an eruption of Mt. Baker would likely not cause significant destruction in British Columbia, there would be secondary effects.  A thick layer of ash would impair the air quality of British Columbia, as well as stress many of their emergency resources.  The risk of volcanic activity is very low, however dramatic seismic activity could change all of that.  



http://www.embc.gov.bc.ca/em/hazard_preparedness/volcano/volcano-hazards-in-bc.pdf

https://www.publicsafety.gc.ca/cnt/mrgnc-mngmnt/ntrl-hzrds/vlcnc-rptn-eng.aspx

http://volcanoes.usgs.gov/volcanoes/baker/baker_geo_hist_115.html

http://www.canadiangeographic.ca/blog/posting.asp?ID=439

Friday, February 27, 2015

Earthquakes in Canada

Canada experiences thousands of earthquakes each year, even if most are not felt on the surface.  Of the 3,900 seismic events recorded in Canada in the last year, only 700 were a 3 or above on the Richter scale.  Of those, only 13 at registered a 5 or higher.  The majority of these events occur on the pacific coast, particularly in British Columbia.  A large earthquake in a densely populated area along the western Canadian coast would be the most destructive and most likely natural disaster to occur in Canada.      


In areas of Canada that are impacted by earthquakes, there strict building codes designed to greatly reduce the risk of structure collapse. However, studies over the last several decades show that you are more likely to be injured by falling or flying household items than to die in a collapsed building.  Because of this, Canada has been promoting “Drop, Cover, and Hold On” in the event of an earthquake.  This technique can prevent injury in the event of an earthquake that causes falling debris.  In addition, it has also been shown that sturdy tables and desks often hold their ground when a building collapses, often supporting the collapsing floor from above.        

The National Building Codes are used to design and constructing buildings to be as resistant to earthquake damage as possible.  While this code is used to take every precaution necessary, there large earthquakes can still cause serious damage to any building.  There are very different sets of standards for western and eastern Canada.  The measures on the west coast are much more rigorous, as the majority of Canada’s seismic activity occurs along the Juan de Fuca, the North American, and the Pacific plates.  



http://www.nrc-cnrc.gc.ca/eng/dimensions/issue8/earthquakes.html

Friday, February 20, 2015

The Plates of Canada

   Along the western coast of Canada, we can see examples of all three types of tectonic plate boundaries.  There are areas that are convergent, divergent, and transform.  There are frequent earthquakes throughout Canada, with the western coast of British Columbia being the most active area.  The three major plates are the Juan de Fuca, the North American, and the Pacific.  Each of these plates interacts with the other in a very unique way.

   The area where the Juan de Fuca plate meets the North American plate is convergent.  The long line of volcanoes down the pacific coast was created by a subduction zone.  The Juan de Fuca plate is slowly shifting under the North American plate, which created the volcanoes Mount Meager and Mount Garibaldi.  This subduction is also responsible for the Cascade Mountains in the United States.  While the most recent volcanic eruption was at Mount Meager over 2350 years ago, there are hundreds of small earthquakes along this line each year.  Currently, the Juan de Fuca plate is locked with the North American plate, causing extreme pressure that could eventually lead to a magnitude 8 or higher earthquake along the British Columbia coast. 

   About 170 miles off the coast of Vancouver, the Juan de Fuca plate meets the Pacific plate.  This meeting is divergent, and is slowly pushing the two plates away from each other.  As this happens, magma from the earth’s mantle fills in the gaps of these breaks in the ocean floor.  Since the two plates are moving away from one another, they are adding to the ocean floor.  There are many small earthquakes along this fault as a result of the plate activity.

   The area where the North American Plate and the Pacific plate interact along the Canadian coast is called the Queen Charlotte Fault.  At this point the North American Plate is moving southeast, while the Pacific plate is moving northwest, which creates a Transform fault line.  The Queen Charlotte fault is very similar to the San Andreas Fault here along the California coastline.  Like the San Andreas Fault, the Queen Charlotte fault is responsible for some of the largest seismic activity ever recorded in Canada.

   The Eastern portion of Canada is located in the center for the North American Plate, and does not fall on any fault lines.  Although it is not on any fault line, each year there are up to 450 earthquakes throughout eastern Canada.  Since these earthquakes do not occur on a major fault line, many are not felt on the surface and as few as 3 per year will be above a magnitude 5.  While the origin of these quakes is bit of a mystery, they have been attributed to weaknesses in the earth’s crust.  The North American plate extends well past the eastern coast of Canada, and results in very little seismic activity.   


This figure represents the seismic activity in Canada in the last 30 days alone (January 20th- February 20th, 2015).  There are 545 recorded examples of seismic activity, however most are a 2 or lower in magnitude, with only 6 reaching a 4 on the Richter scale.
Map of the region / Carte de la region

http://www.earthquakescanada.nrcan.gc.ca/pprs-pprp/pubs/GF-GI/GEOFACT_plate-tectonics_e.pdf

Thursday, February 12, 2015

Canadian Mining and Rock Composition

Canada has a long history of mining minerals, and it continues to be a billion dollar industry to this day.  The minerals mined in Canada include gold, silver, platinum, iron, copper, nickel, diamonds, potash (potassium-bearing minerals), and many others.  In 2014, over $35 billion in minerals were harvested from Canada.  These minerals range from precious minerals like gold and diamond, to the gravel and cement used in everyday life.  

Canada has a variety of both minerals and rocks, as well as some of the oldest rocks in North America.  An area know as The Canadian Shield is made of granite, and contains fossils of bacteria believed to be over 2 billion years old.  The Shield is 1.7 million square miles, and is one of the most mineral rich areas on the planet.  It is the largest area of exposed rock from the Precambrian geologic era 500 million years ago.  Many parts of this granite plateau are covered by either forests and wildlife, or a layer of snow and glaciers in the northern regions.

While many of these mining operations have been going on for over 100 years, I was surprised to learn that the discovery and mining of Diamonds in Canada was a relatively new operation.  While gold has been mined in Canada since the 1800's, the first diamonds in Canada were discovered in 1991.  The Canadian diamond industry has risen to be 3rd in the world, and has received praise for its ethical practices regarding environmental, authenticity, and labor standards. There are many small mining towns throughout Canada, many Canadian citizens support the local diamond and mineral trade.



Sources : http://www.nrcan.gc.ca/mining-materials/publications/8772
                http://geology.com/articles/canada-diamond-mines/
                http://www.canadianshieldfoundation.ca/?page_id=39

Wednesday, February 11, 2015

Hazards, Disasters and Catastrophes:


A Natural Hazard is a natural process and event that has the potential to threaten human life and property.  The process and the events by themselves are not a hazard, but they become a hazard due to human presence on the land.  These events include earthquakes, volcanoes, floods, fires, hurricanes, and tornado.

A Disaster is a hazardous event that occurs over a limited time span, within a defined area.  There are 4 criteria for a Natural Disaster: 1) 10 or more people are killed, 2) 100 or more people are impacted by the process, 3) a state of emergency is declared, or 4) international assistance is required.  If any one of these applies to the process, the event is considered to be a "Natural Disaster."

A Catastrophe is a massive disaster, that requires a considerable amount of time and money to recover from.  For example, the damage from Hurricane Katrina is still evident and the recovery continues almost 10 years after the process.