Green Crab

    The Green Crab found along our shores are  native to the Atlantic Coasts of Europe and North Africa.  his species has the ability to disperse as adults by a variety of anthropogenic and natural mechanisms including: 1) ballast, 2) ship's hulls, 3) packing materials (seaweeds) used to ship live marine organisms, 4) bivalves moved for aquaculture, 5) rafting, 6) migration on surface currents, and 7) movement of submerged aquatic vegetation for coastal zone management initiatives (Introduced Marine Aquatic Invaders, Fisheries of Western Australia).  Green crabs also spread by planktonic transport of larvae and once established in an area can expand their range rapidly (Grosholz 1996, Grosholz and Ruiz 2002).  According to some experts  the Green Crab is one of the more successful invasive predators because they have established large populations on five different continents.
   The introduction of the Green Crab to these many ecosystems has had a negative influence on the soft-shell clams, young oysters, and native crabs in the many areas they live in now.  But the Green Crab is also prey to many birds, larger crabs/lobsters and while they are still young to many fish as well.  There isn't anything one to control the population or to control there impact of Green Crabs because they are not destroying any particular species and they are also prey for many other predators.

Future Consequences of Global Climate Change.

If the current rate of climate change continues then there will be many substantial consequences that will impact our planet.  If the average ocean water temperature continues to increase then the arctic ice caps will continue to thaw and melt at a faster and faster rate.  Also tropical storms and cyclones will intensify in size and strength because they thrive in warmer waters.  Some other consequences may include droughts and hotter, longer lasting heat waves.  Scientists are predicting these future problems from recent events, the warmer our climate has gotten the worse these problems have gotten. Scientists are so confident in their predictions that they are even predicting future consequences of climate change in different continents.  For example:

"North America: Decreasing snowpack in the western mountains; 5-20 percent increase in yields of rain-fed agriculture in some regions; increased frequency, intensity and duration of heat waves in cities that currently experience them.

Latin America: Gradual replacement of tropical forest by savannah in eastern Amazonia; risk of significant biodiversity loss through species extinction in many tropical areas; significant changes in water availability for human consumption, agriculture and energy generation.

Europe: Increased risk of inland flash floods; more frequent coastal flooding and increased erosion from storms and sea level rise; glacial retreat in mountainous areas; reduced snow cover and winter tourism; extensive species losses; reductions of crop productivity in southern Europe.

Africa: By 2020, between 75 and 250 million people are projected to be exposed to increased water stress; yields from rain-fed agriculture could be reduced by up to 50 percent in some regions by 2020; agricultural production, including access to food, may be severely compromised.

Asia: Freshwater availability projected to decrease in Central, South, East and Southeast Asia by the 2050s; coastal areas will be at risk due to increased flooding; death rate from disease associated with floods and droughts expected to rise in some regions." from http://climate.nasa.gov/effects/


Site used:http://climate.nasa.gov/effects/

Volcanic Eruptions.

Most people think that volcanic eruptions would heat the Earth up dramatically but that isn't true. When a volcano erupts it throws out large amounts of sulphur dioxide (SO2), water vapour, dust, and ash into the air. Large amounts of gases and ash can change climates in certain regions for years by increasing planetary reflectivity causing atmospheric cooling. Tiny particles called aerosols are produced by volcanoes. Because they reflect sunlight back into space they have a cooling effect on the world. So there are still somethings that happen on earth that actually cool the earth instead of heating it. The greenhouse gas, carbon dioxide is also produced however the CO2 put into the air by volcanic eruptions is insignificant when compared to emissions created by humans.




















Site used:(http://www.climatechangechallenge.org/Resource%20Centre/Climate-Change/3-what_causes_climate_change.htm#1.)

Ocean Currents.

The oceans are a major component of the climate system. They cover about 71% of the Earth and absorb about twice as much of the sun's radiation as the atmosphere or the land surface. Ocean currents move extreme amounts of heat across the planet - about the same amount as the atmosphere does. But the oceans are surrounded by land masses, so heat transport through the water is through channels. 

Winds push horizontally against the sea surface and drive ocean current patterns. 
Certain parts of the world are influenced by ocean currents more than others. The coast of Peru and other adjoining regions are directly influenced by the Humboldt current that flows along the coastline of Peru. The El Niño event in the Pacific Ocean can affect climatic conditions all over the world.

Another region that is strongly influenced by ocean currents is the North Atlantic. If we compare places at the same latitude in Europe and North America the effect is immediately obvious. Some parts of coastal Norway have an average temperature of -2°C in January and 14°C in July; while places at the same latitude on the Pacific coast of Alaska are far colder: -15°C in January and only 10°C in July. The warm current along the Norewgian coast keeps much of the Greenland-Norwegian Sea free of ice even in winter. The rest of the Arctic Ocean, even though it is much further south, remains frozen. 

Plate Tectonics.

Over the course of millions of years, the motion of tectonic plates reconfigures global land and ocean areas and generates topography. This can affect both global and local patterns of climate and atmosphere-ocean circulation.


The position of the continents determines the geometry of the oceans and therefore influences patterns of ocean circulation. The locations of the seas are important in controlling the transfer of heat and moisture across the globe, and therefore, in determining global climate. A recent example of tectonic control on ocean circulation is the formation of the Isthmus of Panama about 5 million years ago, which shut off direct mixing between the Atlantic and Pacific Oceans. This strongly affected the ocean dynamics of what is now the Gulf Stream and may have led to Northern Hemisphere ice cover.

Glaciers

Glaciers and ice sheets affect and are affected by the Earth's climate change.  They are fresh frozen-fresh water reservoirs that change size when the temperature changes and the amount of snowfall they get.  They are the also the most sensitive indicators of climate change on Earth, growing when the climate cools and shrinking when the climate gets warmer.  But, in the last couple of decades all the glaciers have done is shrink drastically.  One main cause of this is the constant increase in our climate.




For a video showing many different Glaciers and how they shrunk click---->http://news.discovery.com/videos/earth-glacier-comparisions.html