Climate Change

Americans have wide differences of opinion about Climate Change, so rather than taking a position on whether or not Human Caused Global Warming is actually happening, I would like to relate a few observable facts that can be examined directly by anyone who is willing to take the trouble.

Fact 1: C. C. Keeling of the Scripps Institute of Oceanography at the Mauna Loa Observatory in Hawaii, started measuring atmospheric carbon dioxide on a regular basis in the 1950s. His graph of steadily increasing carbon dioxide atmospheric concentrations is shown on the right.

Fact 2: Atmosperic carbon dioxide is transparent to sunlight, but it is opaque to infrared light. After sunlight has warmed the earth, the heat waves cannot escape as easily as the sun's light can arrive. (See diagram above right.) Adding additional carbon dioxide to the atmosphere makes the earth get warmer yet.

Fact 3: Human burning of fossil fuels has increased at about the same rate as the increase in atmospheric carbon dioxide over the same period of time.  The carbon dioxide increases correlate with industrial growth.  Carbon dioxide concentrations in the atmosphere are the highest in 650,000 years. In addition, levels of atmospheric methane, a powerful greenhouse gas, have risen 145% in the last 100 years.  Methane is derived from sources such as rice paddies, bovine flatulence, bacteria in bogs and fossil fuel production.

Fact 4: NOAA has tabulated the hottest years on record in order, since 1901. They used average combined land and ocean annual temperatures to make the table on the right. Of the ten hottest years for this 109 year period, nine were during the last ten years. (1998 was hotter than 2008.)

Fact 5: Hundreds of glaciers are melting and receding on six continents. Only a handful of glaciers are growing. When I was vacationing with my parents in 1950, we drove across the "Going to the Sun" highway. The Grinnel Glacier was huge, and easily seen from the highway. I took a picture of it, with the highway guard rail in the fore-ground.

While vacationing with my wife in 2001, we drove across the "Going to the Sun" highway. This time, the Glacier was not even visible from the highway: we had to hike a significant distance to see the pitiful remnant of it. The black and white aerial photo far left is the Grinnel Glacier in 1938; the color photo near right is the Grinnel Glacier in 2006.

 

Fact 6: Multiple studies show northern hemisphere sea ice to be shrinking at a rate of 35,000 square kilometers annually.  Summer arctic sea ice could disappear entirely by 2033.  From 1958 through 1976 the average thickness of the arctic sea ice was about 3 m, by the years 1993 through 1997 average Arctic sea ice thickness had dropped to 2m. In less than 30 years, more than 30% of the arctic sea ice has melted. Meanwhile, since 2001 Antarctica has been losing about 10 billion tons of ice per year – which is about 10^16 cubic centimeters. The average temperature increase in the Arctic is at least 2C greater than the average increases of the planet as a whole. The Antarctic Peninsula has likewise seen such increases above the planet-wide average of 3C in the last 50 years.

 

Fact 7: Greenland is covered with about 8% of the Earth's grounded ice, but it is melting rapidly.  A NASA survey shows that Greenland lost an average of 82 cubic miles of ice per year from April 2004 to April 2006; compared to 57 cubic miles in 2003, and 27 cubic miles ten years earlier.  Meltwater surging across Greenland’s ice drains to the bedrock, lubricating the giant ice sheet in its ever-faster slide into the sea.  Many climate experts, for example Dr. Klaus Keller, an assistant professor of Geosciences at Penn State, believe that the process may well be irreversible.

It was once believed that collapse of the giant ice sheets in Greenland and Antarctica would take thousands of years, with sea level possibly rising as little as 18 cm by 2100 (about the same amount as the rise in the last century).  However the New York Times has recently (Nov 2010) reported that recent changes in Greenland and Antarctica now suggest that sea level is likely to rise as much as 1 m by 2100 — an increase that will pose a threat to coastal regions the world over. A rise of 1 m will flood low-lying lands in many countries, rendering some areas uninhabitable; coastal flooding that once happened twice a century will happen every few years. It will cause faster erosion of beaches, barrier islands and marshes; and it will contaminate fresh water supplies with salt.  If nothing is done, 15 percent of urbanized land in the Miami area will be under water, and the ocean will encroach more than a mile inland in parts of North Carolina.  Great cities such as New York City, London, Cairo, Bangkok, Venice and Shanghai will all be critically endangered by the 1 m rise in the sea.  However, our understanding of the changes going on is still primitive, and the 1 m rise could very well be an underestimate or an overestimate. Sea-level rise has been a particularly contentious element in the debate over global warming: one peer-reviewed published estimate has suggested that sea level could rise as much as 5 m in this century. (Recent work that produced the 1 m projection was carried out specifically to counter these more extreme calculations.)  And global warming skeptics contend that any changes in the ice sheets are due to natural climate variability, and not to greenhouse gases released by humans.

Some have speculated that there may be a nightmare tipping point just around the corner, where the climate suddenly flips into another ice age. This seems difficult to understand, given the fact that glaciers and polar ice caps are melting, but Fact 7, below, may help one to make sense of this seeming contradiction.

Fact 8: The Atlanic Gulf Stream is one small part of the Great Ocean Conveyor pictured below. Shown in red, it carries warm water from the tropics up to the North Atlantic, where it cools and looses water to evaporation.  Consequently, the Gulf Stream of the far north becomes more dense.  It sinks and heads south (now shown in blue).  The Great Ocean Conveyor stabilizes the temperature of the world’s oceans and indirectly, stabilizes the temperature of the entire world.

But the Great Ocean Conveyor can be stopped "cold". All it takes is a major influx of fresh water, which could come from the melting of Greenland’s ice cap. The last time this happened was about 11,400 years ago.  A vast meltwater lake had formed at the edge of the ice in southeastern Canada.  An ice dam gave way and an enormous flood of fresh water suddenly poured through the St Lawrence River into the North Atlantic, shutting down the Gulf Stream.  This brought back a short ice age known as the Younger Dryas, which has been well-defined by measurements of ice cores drilled from central Greenland.

Fact 9: Coral is dying in the tropical oceans of our planet. The long-term threats to coral are warming oceans and acidification — both of which are at least partly due to climate change. Coral is made up of tiny organisms that join together in colonies, and it depends on a symbiotic relationship with certain species of algae to produce energy through photosynthesis. (It's the algae that give coral reefs their brilliant colors.) But when the water warms — maybe about 1°C to 1.5°C (1.8°F to 2.7°F) above the average high temperature — it throws off that relationship. Eventually the coral reject the algae. What's left is dead white coral.

 

Addressing Climate Change - or Not

It really doesn't matter whether or not a given individual is willing to accept the reality of the Climate Change facts that I have outlined above. Even if the Global Warming Deniers turn out to be right, the reasons for replacing carbon-based fuels -described elsewhere in this website- are still overwhelmingly compelling.
But if one accepts the reality of global warming, it should be even more obvious that carbon-based fuels must be replaced as quickly as possible, and alternatives such as wind, solar, and biofuel can’t do it alone.  We need the the Polywell.  Now.