Tuesday, March 31, 2009

The Housing Boom and Bust

Here's another prophetic article from 2007 on the current housing crisis that helped to collapse the global economy.

The Housing Boom and Bust

NPR.org, April 30, 2007 · Experts cite a number of conditions that have helped fuel the housing bubble of the past several years and are also leading to its bursting. Here we look at some of the top contributors.

Mortgage Lenders

Lenders sold and refinanced homes at historically low lending rates several years ago, pushing up prices. As interest rates rose, these mortgage lenders targeted new customers and used nontraditional products in an attempt to maintain sales. They diversified into subprime lending, loosening lending standards to reach new home buyers. Lenders also expanded the use of exotic loan products – such as interest-only mortgages - across the spectrum of homeowners. Many products used artificially low payments at the start. This encouraged borrowers to buy more expensive homes which further boosted housing prices.

Guy Celela, publisher of Inside Mortgage Finance, offers a defense of lenders. "Delinquency rates were low, home prices were appreciating and the economy was strong." But, he says, the industry participated in "loose, if not sloppy, underwriting." Individuals with extremely poor credit histories received loans. Also consumers received loans that would become unaffordable once the teaser expired or interest rates rose.......


Sunday, March 22, 2009

The Worse Case Scenario

Earth's continents if the polar ice caps melt completely, raising global sea levels nearly 80 meters

Sea levels are rising. And global warming due to the anthropogenic production of greenhouse gases appears to be the primary cause for the gradual increase in global sea levels. Ocean levels are currently rising at about 1.8 mm per year. However, along the US mid-Atlantic and Gulf Coasts, sea levels are rising at approximately 3 mm per year. In the geologic history of the Earth, there is nothing new about changing sea levels. But this may be the first time in the history of our planet that sea level changes may result from human activity.

The new coastline of the eastern half of the United States if sea levels rise nearly 80 meters

The dawn of human civilization coincides with the end of the last ice age and the beginning of a warmer interglacial period. Human civilization also arose during a time of rising sea levels that had already begun before the end of the Pleistocene. Since the termination of the last glacial maximum 20,000 years ago, global seas levels have risen over 120 meters. But an extremely rapid rise occurred between 15,000 and 6,000 years ago resulting in a 90 meter rise in sea levels. But in a mere 500 year period , global sea levels rose an astounding 20 meter (~ 4 meters per century/~ 1 meter every 25 years) just 14,600 years ago. So natural changes in sea level can occur rapidly!

West coast of US after an 80 meter rise in sea levels

Carbon dioxide is the primary anthropogenic greenhouse gas being produced by human civilization mostly through the combustion of coal (35%), transportation fuels (36%), natural gas (20%) and the production of cement (3%). And any increase in anthropogenic global warming also increases the melting and evaporation of water, most significant natural greenhouse gas, which further increases global temperatures and the melting of the ice caps-- and the feedback evaporation of even more water! The latest ice drilling studies in the Antarctic indicate that CO2 levels are now substantially higher than they've been in the last 800,000 years, that's higher than the CO2 levels during an interglacial period some 390 and 550 thousand years ago when sea levels were between 17 to 23 meters higher than today. Just a ten meter rise in sea level would flood coastal regions in the US degree that it would cause the displacement of nearly 25% of the total US population.

South America if sea levels rise 80 meters

Methane is another anthropogenic greenhouse gas that has been steadily increasing in the atmosphere. Methane gas accounted for 20% of the cumulative greenhouse effect form 1750 to the year 2000. And methane gas has a global warming potential 23 times that of CO2 over a 100 year period even though methane only remains in the atmosphere for only about 8 years after decomposing into another greenhouse gas-- carbon dioxide. But humanity may be on the verge of releasing another enormous natural source of this super greenhouse gas.

Since the Industrial Revolution methane concentrations in the Earth's atmosphere has increased by 150% due to human agriculture, landfill creation, and fossil fuels. But these sources of methane are miniscule compared to the quantities of methane that could be released from the huge areas of permafrost on the Earth's surface. These permafrost stores contain vast quantities of carbon from dead plant and animal matter that could decay into methane as they thawed as the result of methane-producing microbes.

Many geologist suspect that it was the rapid release of huge quantities of methane into the atmosphere that caused dramatic increases in global temperatures in Earth's history. It is estimated that the Siberian Shelf alone contains some 1,400 billion tonnes of methane in gas hydrates, which is double the amount of carbon contained in all the plant life on the surface of the Earth. From 1974 and 2000, methane emissions increased by 58 per cent in the part of northern Siberia. The source of this new methane may be from the melting of these northern wetlands which could boost current levels of atmospheric methane ten-fold if it were to totally escape. Permafrost in the Earth's Northern Hemisphere is believed to contain at least 950 billion tonnes of carbon.

Europe if sea levels rise nearly 80 meters

Antarctica, Greenland, and all the other ice caps, ice fields, and valley glaciers contain approximately 32 million cubic kilometers of ice. If global warming caused the ice sheets that cover Greenland completely melted then global sea levels would rise more than 6 meters. If Antarctica's ice sheets should melt, then global sea levels would rise an additional 73 meters. So, in total, if the greenhouse effect from carbon dioxide and methane gas cause all of the world's ice caps, ice fields, and glaciers to completely lose their ice-- then global sea levels could rise more than 80 meters!

Africa after an 80 meter rise in global sea levels

A world completely devoid of polar ice caps would certainly not be the end of the world. But it would a a new world! It would be a world without cities like: New York, Boston, New Orleans, Houston, Washington D.C., Tokyo, Bangkok, London, Rome, Berlin. In the US, states like Florida and Louisiana would be completely underwater along with a good portion of the US Eastern and southern coastal states. California's agricultural breadbasket, the San Joaquin Valley, would once again become the San Joaquin Sea as it was back in the early Pliocene. Nations like Cambodia and Bangladesh would be almost completely underwater. Brazil's mighty Amazon River would be replaced by a huge inland sea.

But new ice free lands would be open for colonization by humanity in Greenland and Antarctica-- for those humans who would like to live in long periods of constant darkness or constant sunlight.

Asia after an 80 meter rise in sea levels

Carbon dioxide polluting fossil fuels are used by human civilization to produce electricity, chemical processing, and for transportation. In the US, only 30% of our electricity is produce from non-carbon dioxide polluting sources. Approximately 71% of the non-carbon dioxide polluting energy in America is produced by nuclear energy, 25% produced by hydroelectricity, and less than 4% by renewable energy resources. Only 20% of electricity in the US is produced from nuclear power while in major countries with more than three times lower per capita-- carbon footprints-- such as Sweden, France who supply 47% to nearly 80% of their electricity through nuclear power.

Australia after an 80 meter rise in sea level

With the coming of electric and Plug-in-Hybrid vehicles, a significant amount of petroleum fuel could be replaced by non-carbon dioxide polluting nuclear and renewable energy resources. Carbon neutral hydrocarbon synfuels can also be produced through nuclear and renewable energy resources. If there are fears about the potential dangers of nuclear proliferation then the nuclear power nations could export synthetic hydrocarbon fuels to nations without nuclear power generators.

But in order to avoid the worse case scenario and to minimize the economic and environmental consequences of climate change and rapid global sea rise on our planet, the world needs to move rapidly and aggressively towards a nuclear and renewable energy economy.

References and Links

1. A sleeping giant? As the planet warms, vast stores of methane — a potent greenhouse gas — could be released from frozen deposits on land and under the ocean. Amanda Leigh Mascarelli reports on the race to understand a ticking time bomb.

2. Meltwater Pulse 1A from Antarctica as a Trigger of the Bølling-Allerød Warm Interval Science 14 March 2003:
Vol. 299. no. 5613, pp. 1709 - 1713
DOI: 10.1126/science.1081002

3. Deep ice tells long climate story

4. Sea Level and Climate (USGS)

5. A +20 m middle Pleistocene sea-level highstand (Bermuda and the Bahamas) due to partial collapse of Antarctic ice

List of countries by carbon dioxide emissions per capita

Greenhouse gases


9. Late Neogene Paleobathymetry, Relative Sea Level, and Basin-Margin Subsidence, Northwest San Joaquin Basin, California

Nuclear Energy Benefits the Environment

Gasoline from Air and Water

Gasoline from Nuclear and Renewable Energy

13. The Plug-in Hybrid Revolution

14. Energy Independence through Nuclear Re-Industrialization

Thursday, March 12, 2009

When Worlds Collide

"Sooner or later disasters such as an asteroid collision or a nuclear war could wipe us all out. But once we spread out into space and establish independent colonies, our future should be safe," Professor Stephen Hawking (2006)

Friday, March 6, 2009

Resurrecting the Delta Clipper

by Marcel F. Williams

"The effort required to resurrect the Delta Clipper program wouldn’t be very great. Many tests showing the proof that the concept works have already been conducted, and the vehicle’s capabilities have already been proven. Therefore, the Delta Clipper is simply a space vehicle nearly ready for use. All that remains is some final testing,building a full-size vehicle, and then putting the spacecraft to work."

Jason Moore & Ashraf Shaikh
Delta Clipper: A Path to the Future

In 1996, Vice President Al Gore and NASA Administrator Dan Golden announced to reporters that had been gathered at the Jet Propulsion Laboratory in California that the successor to America's Space Shuttle would be a revolutionary new Single Stage To Orbit (SSTO) vehicle dubbed “the Venturestar, a reusable spacecraft designed by Lockheed Martin’s Skunk Works. The triangular shaped Venturestar was to be designed to take off vertically, transporting astronauts and up to 27 tonnes of payload into low Earth orbit (LEO) while landing horizontally like the Space Shuttle upon its return to Earth.

But Gore and Golden's choice of the Venturestar came as a shock to many space enthusiast. Most people had expected the Delta Clipper SSTO to be the choice for America's next manned space vehicle especially since the Ballistic Missile Defense Organization in the Pentagon had already successfully tested a small Delta Clipper proto-type that had shown its capability of taking off and landing in a vertical position.

Unfortunately, after several years of technical difficulties attempting to develop the Venturestar and $1.3 billion in Federal expenditures, the project was finally canceled by the Bush administration in 2001.

Eventually, the Ares 1 was chosen by NASA as the successor to the Space Shuttle program and as part of the new Constellation program to return humans to the moon. The Ares 1 will be designed as a two stage vehicle capable of lifting astronauts and payload of 25 tonnes into LEO. The first stage will consist of a solid reusable rocket booster derived from the current Space Shuttle solid rocket boosters. The second stage will utilize a J-2X liquid hydrogen and liquid oxygen rocket booster that will take the astronauts and their payload into orbit. The first human launch of the Ares 1 is scheduled for the year 2014. The last manned missions of the Space Shuttle are scheduled to end in the year 2010. So once the Space Shuttle program ends, there will probably be a 4 or 5 year gap before Americans return to space aboard an American spacecraft. Thank you George Bush!

Critics of the Ares 1 concept argue that we already have launch vehicles capable of doing the job that the future Ares 1 is supposed to do. Although they are expendable vehicles, the US military's Delta IV rockets are already capable of lifting up to 26 tonnes into LEO. Whether such vehicles can be man-rated (capable of safely lifting human passengers into low Earth orbit) is the question. However, there are also questions about whether or not humans would be able to withstand the vibrations that are going to be endured during the launch of humans above a single solid rocket booster aboard the Ares 1. NASA, of course, believes that the Ares 1 can and will be a man rated space vehicle.

This brings us back to the vehicle that Gore and Golden decided not to choose as the Space Shuttle successor, the Delta Clipper. The Delta Clipper was to be designed to take off vertically, go into orbit, and return to Earth by landing in a vertical position. Navigation for the spacecraft was to be provided by global positioning satellites.

In 2008 dollars, the Space Shuttle has been estimated to cost 1.5 billion per launch for 25 tonnes of payload in addition to up to 11 astronauts. But the shuttle was designed to land with only 20 tonnes aboard. If the payload cabin were designed to house an additional 40 astronauts then a round trip flight would cost approximately $29 million per passenger. However, when fully operational, the Delta Clipper was estimated, in 1990 dollars, to cost around $40,000 to 140,000 ($50,000 to $170,000 in 2008 dollars) per passenger. Why so low?

First of all, it takes over 30,000 people to prepare and launch the Space Shuttle. The DC-X test flights, however, only required 15 people to prepare and launch the reusable vehicle.
Once it was fully operational, the Delta Clipper was to be flown almost like a typical commercial airliner. In fact, there were plans to have the Delta Clipper certified by the Department of Transportation, Office of Commercial Space flight and would be able to operate from 'spaceports' located in any state in the union. Sonic booms during take off would have been largely restricted to the spaceport area. And during its return to Earth, sonic booms would have been barely audible since the vehicle would have slowed down to sub-sonic speeds more than 20 kilometers above the Earth's surface. As far as safety is concerned, the fully operational vehicle would have eight or more rocket engines which would provide a safe return engine out capability. And unlike the Space Shuttle, the Delta Clipper would have been capable of landing on practically any flat surface.

The entire cost of developing the first flight certified Delta Clippers was estimated at $5.06 billion, including production of four flight vehicles. And if it had been fully funded in 1991, the first fully operational orbital missions would have began in 1997, and we wouldn't be having this discussion.

The Delta Clipper was originally designed to use liquid hydrogen and liquid oxygen. But there are new fuel concepts that could significantly lower the mass of this VTOVL vehicle. A 50/50 mix of liquid hydrogen and solid methane would require an 8% increase in additional fuel relative to an equal mass of liquid hydrogen which would be more than compensated by a 200% increase fuel density which would substantially reduce the bulk of the fuel tanks.

It would probably cost over 6 billion to develop four fully operational SSTO vehicles, if the Obama administration decided to resurrect the Delta Clipper program today. But the Delta Clipper would revolutionize manned space travel because it would give humans cheap and easy access to orbit. There have already been 6 space tourist that have payed close to or more than 30 million dollars each just to visit the International Space Station. Could you imagine how many wealthy individuals and companies would be willing to pay less than $200,000 to travel into low Earth orbit.

The Delta Clipper could serve as the first component of a cheap and reusable space infrastructure that would allow humans to easily travel to the Moon if reusable space tugs, fuel tankers and lunar landers were placed into orbit by the Ares V heavy lift vehicles. The Delta Clipper could also serve as a reusable Mars landing vehicle if combined with a drag plate to decelerate the vehicle during reentry into the thin Martian atmosphere.

Additionally, the Delta Clipper could serve as a sub-orbital test vehicle for larger future commercial passenger intercontinental rapid transit vehicles capable of traveling to any point on Earth in less than 45 minutes.

While the Ares 1 merely gets Americans back into space, the Delta Clipper would revolutionize manned space travel allowing both NASA and private industry easy and affordable access to orbit and to the rest of the solar system.

References and Links

1. Delta Clipper: A Pathway to the Future

2. DC-X (Astronautix)

3. DC-Y

4. The legacy of DC-X

5. McDonnell Douglas DC-X

6. DC-X Frequently Asked Questions

7. A New Constellation And Its Legacy

8. Single Stage To Orbit (SSTO)


10. Cryogenic Fuels

11. Rockets, not air-breathing planes, will be tomorrow's spaceships

12. Alternate Propellants for SSTO Launchers

13. Frontiers of Space
Philip Bono and Kenneth Gatland (1976)

14. The Constellation Program

15. The Ares 1

16. Cryogenic propellants and method for producing cryogenic propellants

17. A Single-Stage-to-Orbit Thought Experiment

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