Planet Earth Weekly

Climate Change and Renewable Energy: Saving Our Planet for Future Generations


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Our Rapidly Changing World

Our Food Supply may be Rapidly Reduced with Rises in Temperatures.

“There is nothing permanent except change”

Heraclitus , Circa 500 BC

By Dr. John J. Hidore

August 22, 2014—Change through time is a basic attribute of Earth. Earth has been undergoing constant change since it was formed from a cloud of cosmic dust some 4.6 billion years ago. The changes that have taken place and are taking place vary in form, size, duration and areal extent. Days use to be shorter than now; the planet has been both warmer and colder than it is now and the magnetic poles of Earth have changed end for end. Mountain ranges have grown and then eroded away. Ancient seas no longer exist; and biological species have appeared and disappeared. Even the sun which supports life on the planet is not a constant source of energy.

Our Changing Climate

Earth’s climate has changed through time like all else. Throughout most of the history of Earth, the planet was much warmer than it is now. The initial atmosphere contained high concentrations of carbon dioxide and little oxygen. Eventually, the balance between carbon dioxide and oxygen changed to what we have now with much more oxygen. Scattered through time were ages of extreme cold. The earliest ice age took place two billion years ago. The second glaciation took place between 800 and 600 million years ago. This may have been the most extensive glaciation ever to occur on the planet.

Today Our Climate is Changing Faster than at Any Other Time

The global environment is changing now faster than at any time in recent history. What is most significant perhaps is that not only is it changing at a rapid rate but the rate at which it is changing is itself increasing. Simply put the environment in which all living things exist is changing faster and faster. A few examples of current phenomenon will serve to make the point.

Modern humans or Homo Sapien Sapien evolved in Africa some 200,000 years ago. From Africa the species spread out over the planet. It took the modern human species more than a hundred thousand years to reach a total population of one quarter million. We are now adding a quarter million people to the planet each and every day. Each of these added individuals needs food, clothing, and shelter in order to survive. In addition to meeting the needs for survival, they will want many of the amenities of life that are found in the most prosperous countries.

The Rapid Growth of Human Population

Much of the rapid change taking place now is tied to the phenomenal growth of the human population. One of these rapid changes taking place now is the elimination of animal and plant species. There have been times in the past when a large number of species became extinct due to some natural catastrophe. These times are referred to as mass extinctions. Species of plants and animals are now becoming extinct at an extremely high rate. The rate of extinction of species before human development is estimated to have been about one species every ten years. The current rate is at least 100 each year and possibly as high as 1000 each year. Elephants are one species of animal whose numbers are declining rapidly. One hundred thousand elephants were killed in the two years from 2010 to 2012. Satao, the largest known African Elephant was killed by poachers in Kenya near the end of May 2014.

The Monarch Butterfly has Rapidly Reduced in Numbers.

The Rapidly Disappearing Monarch Butterfly

Another example of how fast species are declining is that of the monarch butterfly. Less than two decades ago as many as a billion monarchs migrated to Mexico for the winter. In the fall of 2013, that number dropped to a tiny fraction (1/30) of previous decades. The primary reason for the drop in numbers is the tremendous application of herbicides to agricultural fields. This rapid drop in butterflies is just one of what is now considered to be the sixth mass extinction.

Record Breaking Temperatures

Earth’s climate is being altered by the human species. The planet is warming up due to human activity. The highest average atmospheric temperatures ever recorded for the months of May and June occurred in 2014. The heating is having a profound impact on almost all parts of the environment including the world ocean.

What the outcome of these rapid changes for the human population and other living species is not known. An even cursory look at what is happening on the planet in 2014 suggests that some drastic changes in the behavior of the human population need to take place now.

The only question is whether the people understand and will demand the changes.


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Carbon Dioxide Increases Ocean Acidity

Marine life is threatened because of acidification of oceans.

Shells of marine life are growing thinner due high ocean acidity.

The only way to slow the process is to reverse the addition of CO2 into our atmosphere.

By Dr. John J. Hidore

July 2, 2014—-Prior to the industrial revolution, some 200 years ago, the concentration of carbon dioxide (CO2) in the atmosphere was near 280 ppm. Since the start of the industrial revolution more than 500 billion tons of CO2 has been added to the atmosphere. The concentration of CO2 has now reached more than 400 parts per million (ppm). This is the highest it has been in at least the last 800,000 years, or perhaps longer. Carbon dioxide is now being added to the atmosphere in tremendous quantities. We continue to add about 30 billion tons every year and the amount is increasing. The gas in the atmosphere comes from burning wood, coal, natural gas and other fossil fuels. It also comes from the clearing land of trees and other vegetation.

Most of our planet is covered by ocean. The ocean absorbs carbon dioxide from the atmosphere at the sea surface. It is then circulated downward by the action of waves and currents. In some areas, the added CO2 is found all the way to the sea floor. The world ocean has absorbed some 30% of all the CO2 that has been placed in the atmosphere since the beginning of the industrial revolution. The ocean is currently absorbing about one million tons of CO2 per hour. The capturing of the CO2 by the ocean has reduced the amount of atmospheric heating that is responsible for global warming.

CO2 Dissolves in Ocean to form Carbonic Acid

At the same time that the absorption of CO2 reduces the problem of global warming, it causes substantial damage to ocean life. The carbon dioxide dissolves in the ocean to form a weak carbonic acid. This process is acidifying the world’s oceans faster than at any time in the last 300 million years. The acidity is now about 30% higher than it was a couple of hundred years ago. If the present rate of growth in acidity continues, the ocean’s acidity could become double what it was 200 years ago. There does not seem to be any practical means of removing the acidity form the ocean, so it will be with us for the foreseeable future.

CO2 in our atmosphere is linked to ocean acidity.

The acidity of our oceans is threatening ocean life.

Shelled Organisms in Our Oceans are Declining

The effects of the increasing acidity has widespread impact on many marine organisms, from the very smallest to the largest. Carbonic acid dissolves calcium carbonate. Many marine organisms have shells or external skeletons which depend on calcium carbonate to build these structures. Researchers are finding that shelled microorganisms, that form the basis for the marine food chain, are declining. Greater amounts of acidity in the sea prevents the formation of new shells and dissolves existing ones, such as coral. Among the creatures affected by the acidification include oysters, clams, and crabs. The barnacle, which is often found on dock pilings and the hulls of ships, is another example.

The negative effects on sea creatures with calcareous shells have already been well documented. Coral reefs are an identifying feature of the tropical oceans. These reefs depend on the growth of small organisms with calcareous shells. As the sea becomes more acidic, there is less and less carbonate available to form the shells. Some reefs such as the Great Barrier Reef off the Australian coast are already being affected. If our present policies on the use of fossil fuels and continued economic growth persist, coral reefs may begin to break up within the next 40 years.

Increased acidification in the ocean, or parts of it, may become too severe to support the microorganisms which are the base of the oceanic food chain. Acidification along parts of the Oregon coast is already so severe that it has cut oyster production in half. The increased acidity stunts the growth of the oyster larvae.

The Rapid Rate of Ocean Acidification

Unless acidification is reduced, large areas of the sea floor in shallow water and reefs will be covered with a mat of algae by 2100. There seems to be little chance of halting the process without a major change in policy to slow global warming. In the past there have been times when atmospheric CO2 was higher than it is now. Past changes in the level of carbon dioxide tended to take place fairy slowly. The present rate of increase may simply be too rapid to enable many marine plants and animals to adapt. The only way to slow the process is to reverse the addition of CO2 into the atmosphere.

This will take a global response to reduce fossil fuel use.


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The Impact of Disappearing Ice Shelves

Melting of the Ice Shelves

Ice shelves are quickly melting in both the Arctic and Antarctic.

By Dr. John J. Hidore

The rapid melting that has taken place in recent decades suggests that with increased temperatures in coming decades there will be rapid melting of the ice shelves and more rapid advance of the glaciers that will cause a rise in sea level.

May 18, 2014—Near Earth’s north and south poles are the coldest areas on the surface of the planet. The area around the North Pole is referred to as the Arctic and that around the South Pole as the Antarctic. The reason these two areas are so cold is that during the course of a year they receive much less solar energy than areas nearer the equator. While they are both very cold regions, the Antarctic and the Arctic are fundamentally very different from each other. The Arctic is largely a sea surrounded by land. On the other hand, the Antarctic is a continent surrounded by sea. While they are basically very different geologically, they have many things in common. One, of course, is that they are very cold environments. Both have large ice sheets and moving glaciers. Another less known feature found in both regions is the ice shelf. Ice shelves are masses of floating ice that are frozen to the seashore. They originated as parts of continental glaciers that slowly flowed off the land and began to float. Though they are floating they are anchored to land.

The Arctic Shelves

Most of the ice making up these shelves is more than 3000 years old. Since their discovery in 1906, these ice shelves have lost 90% of their ice. Some of the ice shelves that existed in 1906 are entirely gone and others are on the verge of melting away. The largest known ice island found in the Arctic Sea is one that broke from the land in 1956. Most of the melting of these ice shelves has taken place in recent decades. In 2005, the Ayles ice shelf was just one of several remaining in the Arctic region of Canada. That year the entire ice shelf broke free from Ellesmere Island. The island is approximately 500 miles south of the North Pole. In fact, using a combination of satellite imagery and seismic data, researchers were able to determine that the shelf actually broke away the afternoon of August 13, 2005. Within a few hours the mass had formed a new ice island, trailing bits of broken ice. The ice island drifted some 30 miles out to sea and then became frozen into the sea ice.

August 2008, the Markham Ice Shelf detached from Ellesmere Island and floated away. Two large pieces of ice also detached from the Serson Ice Shelf, reducing the over-all size of the shelf to less that half what it was the previous winter. It is now largely gone. The Ward Hunt Ice Shelf is also breaking up. It lost 10% of its area in the summer of 2008.

One important aspect worth noting is the breakup of these ice shelves will not have a major effect on sea level since they are already floating in water. Ice floats in water because ice is less dense than water. When water freezes it expands some nine percent, making it less dense than sea water. So when the ice melts its density increases to that of the surrounding sea water. Thus the volume of water does not change. There is actually a slight change due to the difference in density of fresh water and sea water.

Antarctic Ice Shelves

Ice shelves along the West Antarctic Peninsula are either rapidly melting or have broken up altogether. These ice shelves have always shed icebergs. Large pieces of ice occasionally break off the edges of these floating ice masses and drift away from the land mass. In March of 2000, the second largest iceberg ever measured broke free from the Ross Ice Shelf and floated into the Ross Sea. The huge iceberg, B-15, was about 180 miles long and 18 miles wide. Within a week of this iceberg’s formation, three more large pieces broke free from the ice shelf.

Ice Shelves: Melting at an Ever Increasing Rate

Three of the ice shelves disintegrated in the last decade of the 20th century. Many of the ice shelves located on either side of the peninsula have been melting at an ever increasing rate. These ice shelves are the Prince Gustave Channel, Larsen A, Larsen inlet, Muller Ice Shelf, and Wilkins Ice Shelf. Larsen B and Wilkins lost 1180 square miles of ice in just two years from 1998 to 2000. In 2002 a section broke from the Larsen Ice Shelf that was 1200 square miles in size. On February 28, 2008, a large piece of ice broke from the edge of the Wilkins ice shelf. In contrast to the huge pieces breaking off from the Ross Ice Shelf, these shelves are disintegrating in small pieces, which is usually the case with warming temperatures.
Ice shelf     Location                             Year                          Size                 ________________________________________________________________________
Ayles                 Arctic                             2005                       41mi2

Larsen A         Antarctic Peninsula   1995                   1620 mi2(4200km2)

Larsen B          Antarctic Peninsula   2002                   1200 mi2 (3100 km2)

Markham               Arctic                        2008                  19 mi2 (49 km2 )

Ross                         Antarctic                   1987                 1834 mi2 (4,750 km)

Ross                        Antarctic                      2000              4,250 mi2-11,000km2

Serson                    Arctic                            2008              lost 50% of area

Ward Hunt            Arctic                           2003              150 mi2 (384 km2 )

Wilkins                   Antarctic                       2008              160 mi2 (416 km2 )

______________________________________________________________________

Collapse of Ice Shelves

What is of most concern is how the breakup of these ice shelves will affect the continental glaciers that are driving the ice shelves seaward. Since ice shelves are anchored to land they hold back the continental glaciers from advancing seaward. It is possible that the removal of these ice shelves will result in more rapid advance and faster melting of the glaciers. The Ross Ice Shelf is an example. It is one of the largest shelves on the West Antarctic ice sheet. The tides lift and lower the shelf twice a day. During high tide the shelf is lifted, there is less friction with the sea floor beneath, and the glacier behind moves forward. At low tide the rate of movement is slowed. Melting of the Ross Ice Shelf would allow the glaciers behind to move forward adding ice to the sea and raising sea level. Winter temperatures in the area have increased some 9 ºF (5º C).

The rapid melting that has taken place in recent decades suggests that with increased temperatures in coming decades there will be rapid melting of the ice shelves and more rapid advance of the glaciers that will cause a rise in sea level. How much sea level will rise depends on many factors which are hard to predict.