Beach House for Sale—Cheap

The historic trend of rising sea-levels during the period of the industrial revolution and into Recent_sea_level_rise_1modern times is unmistakable.  For beach lovers, let me make just one suggestion, don’t buy that beach house now.  The price will be coming down soon.

Scientists are now re-projecting their estimates of sea-level rise while you can see their current projections at the IPCC website:

Predicting sea-level rise is a complex problem because the various climatic and ecological factors influencing sea-level rise all seem to be operating at a different pace with varying levels of predictability.

The existing climate models with their sea-level projections do factor in a range of human responses from “business as usual” to various carbon dioxide control strategies.  What humans do in the days ahead will either add to the problem or slow the pace of global warming and sea level-rise.

Sea Level Rise Projections to 2100

Source: IPCC Third Assessment Report (2001).

Just as a pot of water expands as it is heated, so the oceans will expand as the water warms.  Humans have warmed the oceans almost by one degree and a second degree is largely in the pipeline.  The IPCC models will have little difficulty predicting the range of changes caused by predicted warming with a fair amount of certainty.

Mountain-top ice formations around the world are melting at a measurable but increasing pace.   Artic ice is shrinkage at an alarming pace. Since it is floating ice, this melt does not add to the ocean directly but the snow and ice loss decreases albedo increasing energy absorption and thereby causing a feedback that leads to ever warmer surface temperatures.  The scientists have taken these factors into consideration in their climate modeling with increasing accuracy.

Thawing of permafrost all across the polar region will increase the decomposition of widespread high-latitude peatlands, significantly increasing the rate of CO2 and methane escaping to the atmosphere.  This is of particular concern in Siberia where there is estimated to be 70-80 billion tons of trapped methane that is beginning to escape into the atmosphere at a rate five times what was earlier predicted. Atmospheric methane could also come from breakdown of clathrates which are frozen gas hydrates that have been stored beneath the vast Arctic continental shelves.  Changes in predicted methane releases are not following earlier scientific estimates and their potential powerful influence on the climate system can create a significant amount of uncertainty for predicting future sea-level rise.

I look forward to seeing how the upcoming IPCC final report handles these questions in light of recently published science.

Ten years ago, Greenland was spilling an excess of water equal to one Nile River.  Today, Greenland loads about three Nile Rivers into the ocean each year.  Most troubling, Greenland is experiencing a dramatic increase the number and magnitude of ice quakes as large blocks of ice begin to move.  One six cubic mile block of ice got my attention when it slid 42 feet in under a minute. At best, the melting of ice on Greenland will be non-linear.  Worst case, Greenland begins to calve massive ice formations into the ocean.  The same kind of pattern is happening in West Antarctica.

How can scientists accurately predict mass ice failures?

Forests particularly boreal forests are an important carbon sink that are being threatened.  Insects that over-winter in mild conditions are causing extensive damage and recent studies suggest forest fires are four times as frequent and burn six times as much land area as they did a few years ago.  We risk turning important forest carbon sinks into troubling carbon sources.

Forest scientists, particularly wood scientists, can calculate how much load a tree limb can handle before it breaks but they are unable to accurately predict when multiple human-made forces act synergistically, overtake and cause a forest ecosystem to collapse.  Forests are noisy systems with too many moving parts.

All of the above climate-forcing mechanisms will have global climate consequences.  Some will increase greenhouse gas loadings which in turn will amplify the warming processes.  Melting ice tends to increase the absorbtion of energy which further accelerates additional ice melting and the expansion of water leading to sea level rise.

Until last September 1st, two million people lived in coastal Louisiana within two feet of sea level.  The same development pattern occurs up and down our coasts.  While it is generally understood that twenty-feet of sea-level rise will trigger catastrophic socioeconomic dislocations and millions upon millions of environmental refugees, a sea level rise two feet will displace millions of Americans, do extensive damage to the built environment and destroy millions of acres of coastal wetlands.

It is easy to jump to the false conclusion that uncertainty makes inaction an acceptable option.  Make no mistake about it; sea levels will be rising dramatically if we do not act now. The only real question is how much and how fast?  We can slow the pace of sea level rise if we are willing to act to wean carbon fuels from our energy diet.  There is no time to waste.

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Published: November 28, 2006