Global warming and the biblical flood

By now most people are familiar with the projected near term effects of global warming – rising average temperatures, melting mountain glaciers, melting of the northern polar ice cap, rising sea levels, increased flooding and more severe droughts, species extinction and spread in the range of other species that may cause disease or affect local native species, etc.

These are short term effects, because they are reversible simply by reducing the level of CO₂ and other greenhouse gases in the atmosphere. However, if we do not address global warming and continue to permit average temperatures to rise, the world will reach what is described as a tipping point in which even more dramatic changes will take place. Once we pass the tipping point these changes will be increasingly difficult and expensive to reverse, and we may simply have to live with and adapt to them for centuries or millennia. Unfortunately, we do not have a long time to go before a tipping point is reached. Some estimates are on the order of about 20 years.

It is these long range effects of global warming that will occur after a tipping point is reached that will be described in this article. My conclusions are based on data on natural climate change over the last few hundred thousand years.

I became interested in the effects of global warming while writing a book about Biblical history. The book, entitled Understanding the Exodus, explores through science, archeology and history the major events affecting the evolution of the Jewish religion.  

The Bible is a book of legends. Legends are stories that have been told and retold orally for generations before they are finally written down. Some legends are myths and others may have a core of truth that may be highly embellished. In the case of the Bible these stories are usually written down by someone with a religious or political agenda. The Bible is, therefore, not a scientific work, and extracting factual information from it is something of an art.

The biblical legend that has the most relevance to the subject of global warming is the story of the flood in the Book of Genesis. This flood, if it occurred, could have been a dramatic example of an effect of climate change. If it occurred, it occurred during the stone age, and it was an event that was so traumatic that memory of it was preserved in legends for thousands of years until it was written down. Two legends in which the story is preserved are the biblical story of Noah and the Babylonian legend of Gilgamesh.

To see if the flood legend is related to an actual event and determine whether that event was related to natural climate change, we need to answer a few questions:

What evidence is there that a great flood really occurred?

If there was a flood, when did it happen?

Why did it happen?

How is this flood related to climate change?

As a starting point we should note that the ice age in the Northern Hemisphere ended and the glaciers covering the continents in the Northern Hemisphere receded about 10,000 years ago. In this article we will investigate when and why this ice age began and why it ended.

About 2500 to 3000 years after the end of the last ice age we have evidence of a massive flood in the Middle East, which probably affected other parts of the world as well. A map of the Middle East region is shown in Figure 1.

                                                Figure 1. Map of the Middle East

                        Source: www.geographicguide.net/asia/middle-east.htm

There is evidence from erosion and radiocarbon data of a massive flood in the Negev Desert about 7500 years ago. About the same time there is evidence from erosion data of a massive flood in the Gulf of Suez. In the Persian Gulf evidence was also found of a massive flood at about the same time. References to this evidence are given in Understanding the Exodus.

 The most dramatic piece of evidence for the biblical flood is the flooding of the Black Sea Basin, which before the flood was separated from the Mediterranean by over 160 km (100 miles) of land. Given all of this evidence for a flood, it is likely that the Biblical flood was based on an actual flood whose survivors passed the story of the flood down for generations until it was written down.

What could have caused such a flood? While both the biblical and Babylonian flood stories describe a storm, this part of the world does not have the topography to support massive cyclonic storms. If the cause of the flood were a storm, victims of the flood would have been washed out to sea, whereas in both flood stories the survivors are washed inland. Both flood stories provide a clue to the true cause of the flood, because they say, in addition to rain, water just appeared out of the ground.

“All the outlets of the vast body of water beneath the earth burst open” (Genesis 7:11)

Where did all this water come from?

In Understanding the Exodus I indicated that the most likely cause of such a flood would have been the rapid movement of a large body of ice from the Antarctic continent into the ocean. This would have caused a huge tsunami and a large, long-lasting rise in sea level that could have caused the flooding that occurred in the biblical flood story. The evidence for a large movement of ice into the ocean is the disappearance of a large fraction of the Western Antarctic ice sheet about the time of the flood. This phenomenon appears to have been the last act of the last ice age.

The effect of a tsunami and rise in sea level could be amplified by the channeling of ocean water into narrow inlets. Water is basically an incompressible fluid. If the same amount of water is forced to pass through narrower and narrower openings, it must either move faster or the height of the flowing water must increase. In either case when it finally hits land it will pile up to a height much greater than in the open ocean. This would be the case if water pouring into the Red Sea is channeled by the Sinai Peninsula into the Gulf of Suez and the Gulf of Aquaba (Figure 2).

In the Gulf of Aquaba water could pile up high enough to overcome the 200 meter (600 foot) barrier between the Red Sea and the Dead Sea Basin, submerging the area from the Sea of Galilee to the Negev. This land barrier is shown in the map of Figure 3.

What could have caused the ice cap to slide off the Western Antarctic continent into the ocean? The ice age in the Northern Hemisphere ended about 10,000 years ago. During the ice age mountains of ice miles high piled up on the continents. When this ice melted and the glaciers receded in the Northern Hemisphere, huge quantities of water were released into the oceans raising the level of the oceans. Glaciers in Antarctica, which were previously located above sea level had part of their bases submerged as the ocean level rose. This reduced the friction between the land and the glaciers and made the glaciers less stable. An effect that could further destabilize these glaciers, such as a volcanic eruption under the ice, could trigger the glaciers to rapidly slide off the Western Antarctic continent.

                                                   Source Google maps.

This may explain the cause of the biblical flood, but it fails to explain what caused the ice age in the first place and what caused the ice age to end. It also is not clear what, if any, connection this flood has to global warming.

To connect the biblical flood to natural global warming we first must understand how global warming can trigger an ice age in the Northern Hemisphere. If global warming results in the melting of the northern polar ice cap so that the Arctic Ocean becomes ice free in summer, the open ocean will absorb much more solar energy than the ice cap previously did. Only about 10% of the solar energy incident on the polar ice cap is absorbed. The rest is reflected back into space. Once the ice cap melts, 90% of the solar energy incident on the open water will be absorbed and only 10% will be reflected back into space. This makes it very difficult for the Arctic Ocean to refreeze once the ice cap has melted. Therefore, the tipping point for climate change will be reached when global warming causes the Arctic ice cap to melt and the Arctic Ocean becomes open water.

Some climatologists believe that melting of the northern polar ice cap will affect the Gulf Stream current. The Gulf Stream is a warm ocean current originating in the Gulf of Mexico that flows north along the coast of Western Europe moderating the climate of countries along this coast. Great Britain is at about the same latitude as Labrador in Canada, but has a much milder climate due to the Gulf Stream.

As the Gulf Stream flows north its waters gradually cool. When the Gulf Stream reaches the Arctic Circle some of the water in the Gulf Stream freezes. This ice does not contain salt, so the remaining water that does not freeze becomes saltier and denser and sinks to the bottom of the ocean where it becomes part of a cold return current that flows south back to the Gulf of Mexico. There is a concern that if the water in the Gulf Stream does not freeze, the cold return current will cease to flow, which may prevent the Gulf Stream from flowing north and lead to a cooling of the climate of Western Europe. However, there are other mechanisms that could keep the Gulf Stream flowing even if the cold return current ceases to flow or is greatly diminished.

If the cold return current is diminished or ceases to flow entirely, the waters of the Gulf Stream will become warmer because the cold return current is not available to moderate the heating effect of the tropical sun on the equatorial ocean. Also, as the polar ice cap contracts, the Gulf Stream will have to flow farther and farther north before its waters begin to freeze. If these waters do not freeze at all, it is possible for this current to continue to flow across the Arctic Ocean, coming out through the Gulf of Alaska and the Bering Sea into the Pacific Ocean (See map of the Arctic Ocean in Figure 5). Even if this does not happen, the waters of the Gulf Stream will increase warming of the Arctic Ocean surface and increase the rate of evaporation of surface water into the air. Evaporation can remove water from the Arctic Ocean permitting additional water from the Gulf Stream to flow north without raising the level of the Arctic Ocean. Evidence that the Gulf Stream did not cease to flow during the last ice age is the existence of cave art in Spain and France from about 40,000 years ago when the Northern Hemisphere was in the middle of an ice age.

                        Figure 5. Topographical map of the Arctic Ocean

                        Source: geology.com/world/arctic-ocean-map.shtml

This still does not answer the question of how global warming can result in an ice age.

Most people in the American Midwest are familiar with the phenomenon of lake effect snow. Lake effect snow is produced when wind blowing over a large open body of water, like one of the Great Lakes, picks up moisture and then deposits it on land as precipitation. In the winter this precipitation will take the form of snow. If the Arctic Ocean becomes open water, wind blowing across the ocean can pick up large quantities of moisture and deposit this moisture on the adjacent continents. While the water of the Arctic Ocean may have absorbed solar energy that prevented it from refreezing, the land masses in the Arctic would still be cold, and in the winter precipitation would fall in the form of snow. Because the Arctic Ocean is much larger that the Great Lakes, several meters of snow could be deposited on northern land masses during the Arctic winter.

During the summer this snow cover will begin to melt. However, as long as it remains, about 90% of the solar radiation incident on it will be reflected back into space. Without the snow cover virtually all of this radiation would be absorbed by the land. If the snow cover is deep enough it may not completely melt during the summer, and winter snows would continue to build up from year to year, compacting the snow cover into glacial ice. The glaciers that are produced would migrate southward as they grew due to the rotation of the earth and centrifugal forces. Therefore, one effect of global warming would be to replace the Arctic polar ice cap as a mechanism for cooling the earth with ice covering the northern continents, which also cools the earth by reflecting solar radiation back into space. 

How long will this accumulation of ice on the continents of the Northern Hemisphere continue? As long as there is open water in the Arctic Ocean. Water that evaporates from the Arctic Ocean is replenished by inflows from other oceans. Accumulation of ice on the continents can continue for tens of thousands of years and the glaciers can become miles thick. If this were to happen as a result of current man-made global warming, large land areas of the Northern Hemisphere would eventually become uninhabitable and would have to be abandoned. This would include Alaska, Canada, Northern Europe and Siberia. Previous ice ages also covered the northern part of the continental United States.

As long as more snow accumulates every year than melts, the amount of snow on the continents will grow. This process gradually drains the oceans leading to a drop in sea level and exposure of the continental shelves of continents worldwide. During the last ice age sea level dropped about 130 meters (about 425 feet) relative to its present level. The drop was large enough to cut off the Mediterranean and Red Seas from the world’s oceans and reduce them to strings of highly saline salt water lakes. As sea level began to rise and flood these basins, the high salinity lakes remained at the bottom of the Mediterranean and Red Seas because their water was denser than ambient ocean water. These regions of high salinity continue to exist at the bottom of these seas to this day.

About half of the area of the Arctic Ocean is continental shelf (See Figure 5). As sea level continued to drop during the last ice age and the Arctic Ocean continental shelf was exposed, the area of the Arctic Ocean decreased, its openings to the world’s other oceans were reduced, and the Arctic Ocean was gradually reduced to an inland sea. Exposure of continental shelves also increased the amount of land available for snow cover and reduced the light energy absorbed by the earth. As the ice age continued and the globe continued to cool due to ice cover on the continents, the Arctic Ocean gradually refroze. When the polar ice cap refreezes the snow machine, the mechanism by which snow is deposited on the northern part of the continents of the Northern Hemisphere, will be shut down, and the glaciers will begin to melt more rapidly than they are supplied with new ice. The retreat of the glaciers heralded the end of the ice age in the Northern Hemisphere and a gradual rise in sea level as a result of melting ice and snow.

So the primary requirement for the development of an ice age in the Northern Hemisphere is that the Arctic Ocean remain substantially ice free most of the year. During these periods of open water, winds can carry moisture to land where it would be deposited as snow. Because the continental areas above the Arctic Circle are cold practically all year round, snow could be deposited most of the year and accumulate from year to year. The polar ice cap can only melt as a consequence of global warming. Therefore, global warming is a prerequisite for the development of an ice age.

 

Figure 6. Topographical map of Antarctica. The light blue areas on the map are below the present level of the ocean surface. (Source: Wikipedia > Antarctica > Geology)

This reduction of friction could enable at least part of the ice cap to slip off the continent and into the ocean producing a large rise in sea level and an enormous tsunami. The last time this happened was about 7,500 years ago creating the Great Flood of antiquity. With the current sea level, the time required for a critical ice mass to build up to a level where it could become unstable and slide into the ocean again is estimated to be about 7000 years. This would mean that we are about due for another massive flood in the next century or two. This flood would raise sea level less than the biblical flood because less ice has had time to accumulate on the Antarctic Continent. PBS (public television) had a program on this subject that first aired on April 21 1998. You can find information about it at

http://www.pbs.org/wgbh/nova/transcripts/2508warnings.html.

We have seen how natural global warming can produce an ice age in the Northern Hemisphere, which in turn leads to global cooling, which eventually causes the ice age to end due to refreezing of the Arctic polar ice cap. Should we expect that the increase in greenhouse gases due to human activity will have a similar effect? We expect the northern polar ice cap to melt within the next few decades creating an Arctic Ocean that is ice free most of the year. After the earth’s climate reaches this tipping point the snow machine will be turned on and the northern parts of North America, Europe and Asia will be covered with snow. Glaciers will form and spread south. Alaska, Canada, Scandinavia, Northern Europe and Siberia will eventually have to be abandoned. High levels of CO₂ may slow the advance of the glaciers but not stop the process. Unfortunately, even reducing CO₂ in the atmosphere will not stop the process since it would reduce the melting of the glaciers by reducing global warming. The cooling produced by the polar ice cap will be replaced by cooling produced by snow and ice on the continents. Rising sea levels due to global warming will be replaced by falling sea levels. Continental shelves will become exposed and some will be covered with ice.

Figure 7. Variation of earth’s orbit, mean global temperature and mean global carbon dioxide level. Source: National Geographic Magazine, September 2004

This graph shows that periods of natural global warming and cooling are correlated with variations in the earth’s orbit around the sun. The upper line in the graph indicates the variation in ellipticity of this orbit. Periods of global warming are associated with the earth’s orbit becoming more elliptical and periods of global cooling are associated with the earth’s orbit around the sun becoming more circular. The amount of CO₂ in the atmosphere is also correlated with the variation in earth’s orbit. 100,000 year periods in orbital variation appears to be superimposed on a longer 400,000 year periodic variation.

What causes this periodic variation in the earth’s orbit around the sun? The primary cause is the gravitational interaction between the earth and the moon. The daily variation in ocean tides is a result of the gravitational pull of the moon on the earth. As the earth’s orbit varies around the sun, the moon’s orbit also varies by a compensating amount, so that the overall earth-moon system remains in a stable orbit around the sun. The variation in earth’s orbit around the sun caused by its interaction with the moon is a small fraction of the distance between the earth and the sun. By itself, this variation in the distance between the earth and the sun would not be enough to cause the climate variations shown in the data. For these orbital variations to cause such dramatic climate variations they must be driving and amplifying other processes that affect climate change.

It is possible to understand how average global temperature might vary slightly with small variations in the earth’s orbit. If, as a result of a more elliptical orbit, the earth were somewhat closer to the sun during summer and winter and a little farther from the sun during spring and fall, the peak high temperature during summer might be slightly higher, the average temperature during winter could be slightly warmer, and average temperatures during spring and fall might be slightly cooler. Overall, there might be a slight warming trend. This small variation in temperature due to variation in the earth’s orbit would not be enough to cause the polar ice cap to melt.

Nevertheless, it is a fact that global cycles of warming and cooling do occur with the same periodicity as the variations in earth’s orbit. We see from this data that as earth’s orbit becomes more elliptical both mean temperature and atmospheric CO₂ levels rise and the earth enters a warming period. Alternatively, as earth’s orbit becomes more circular mean temperatures and atmospheric CO₂ levels begin to fall and the earth enters an ice age. Warming periods are relatively brief in geological time, from 10,000 to 20,000 years, whereas ice ages tend to last for 80 to 90 thousand years. Therefore, if the earth enters an ice age it is likely to remain in one for a very long time.

Looking more closely at the data of Figure 7 raises some questions, however. If we compare the times at which warming occurs with the periodic  variation of the earth’s orbit we see that temperatures peak and begin to fall well before the peak in ellipticity of the earth’s orbit that is supposedly responsible for the temperature rise.  This should not be the case if the change in mean temperature is solely the result of the change in the earth’s orbit around the sun.

Another problem with understanding the data of Figure 7 is that as the earth’s average temperature increases the level of CO₂ in the atmosphere increases. One would think that natural global warming would result in a greater amount of vegetation that would tend to decrease the amount of CO₂ in the atmosphere as average temperatures increase.

A simple experiment can explain why CO₂ levels might rise with increase in atmospheric temperature. Take two 2-liter bottles of a carbonated beverage like club soda. Carbon dioxide has been injected under pressure into these beverages and has dissolved in the liquid. Place one of these bottles in a tub of ice water and the second in a tub of bath water about 80 – 90° F and let the temperature equilibrate in the two bottles. Then open both bottles. The cold beverage will stay in the bottle until you pour it out. The warm liquid will generate bubbles that overflow the top of the bottle.  This occurs because warm water can absorb less CO₂ at a given air pressure than an equal amount of cold water.

During an ice age average ocean temperatures become colder and a large quantity of CO₂ from the atmosphere can dissolve in the oceans. This continues for tens of thousands of years. But as the earth’s orbit becomes more elliptical, average global temperatures begin to rise slightly. This slightly heats the oceans and releases some CO₂. The warming effect of additional CO₂ in the atmosphere amplifies the small warming effect caused by the change in the earth’s orbit. Every year there will be slightly more CO₂ released by the oceans into the atmosphere and a slightly higher average global temperature, so that temperature will rise in direct proportion to the increase in the amount of atmospheric CO₂. During a warming period CO₂ from the oceans will increase atmospheric CO₂ even though increased vegetation on land is absorbing some of that CO₂.

The freezing of the Arctic polar ice cap towards the end of an ice age coupled with the natural temperature rise due to changes in the earth’s orbit and the release of CO₂ from the oceans into the atmosphere was responsible for the retreat of the glaciers in the Northern Hemisphere. As warming continued it also began to melt the polar ice cap. Once the polar ice cap melted, snow on the continents of the Northern Hemisphere began to accumulate, resulting in a geologically rapid drop in average global temperature. This drop in temperature occurred more rapidly than the fall in the level of CO₂ in the atmosphere.  The snow cover on the continents of the Northern Hemisphere grew with time which led to the onset of an ice age. An ice age gradually cools the oceans’ waters leading to absorption of CO₂ from the atmosphere and a further acceleration in global cooling.

From the graph of Figure 7 we see that the shortest period of natural global warming occurred when the earth’s orbit was most elliptical and heating of the atmosphere occurred most rapidly. The periods of global warming before and after the cycle of peak ellipticity in the earth’s orbit were longer than for the cycle of peak ellipticity . We are now living in a cycle of the earth’s orbit which is the most circular of the last 400,000 years. Therefore, we would expect natural global warming to occur at the slowest pace in 400,000 years so that the period of moderate temperatures would continue for the longest period of time.

In fact, we can see from Figure 7 that we have already passed the peak of this cycle without the polar ice cap melting due to natural causes. Without man-made global warming it is possible that another ice age would not occur during this orbital cycle, so that without human intervention we could have avoided an ice age during this natural climate cycle. Unfortunately, as a result of the industrial revolution, we have doubled the amount of CO₂ in the atmosphere compared with the amount that would be expected from natural causes, creating a situation in which melting of the polar ice cap cannot be prevented and the onset of another ice age cannot be stopped. The world will now be forced to first endure a rapid period of global warming with all of its accompanying detrimental phenomena followed by a much longer period of global cooling leading to a new ice age.

Stabilizing earth’s climate

Correcting the damage inflicted by humans on the earth’s environment and climate will be both long and expensive. Converting from fossil fuel to sources of energy that put less or no additional greenhouse gases into the atmosphere will not come soon enough to prevent the northern polar ice cap from melting or to reduce atmospheric CO₂ to preindustrial levels. The goal of humanity in combating global warming should not simply be to reduce greenhouse gases in the atmosphere, but to develop a plan for long range stabilization of earth’s climate.

We would prefer to have a stable temperate climate in the Northern Hemisphere rather than another ice age. This can only be done by putting the carbon we have extracted from the earth back into the earth in stable configurations that could not spontaneously return to the atmosphere. For example, injection of liquid CO₂ into deep wells in the ground may not be a good method of carbon sequestration because it may be possible for the CO₂ to return to the atmosphere as a result of leaks or massive earthquakes. Other methods of carbon sequestration appear to be more promising.

Generating new petroleum

Even though it will not prevent the onset of an ice age, it will be necessary to reduce greenhouse gases in the atmosphere on a massive scale as a first step toward climate stabilization. One possible way of doing this would be to create the conditions for the formation of new petroleum deposits. These deposits would take many years to produce petroleum, but the objective is not to create petroleum for fuel, but to develop a stable way to sequester carbon in the earth. Petroleum remained in stable deposits in the earth for millions of years before humans developed the technology to extract it.

To create conditions for the formation of petroleum deposits we need to understand how petroleum is generated naturally. A precondition for the generation of petroleum is the creation of dead zones in coastal bodies of water. Dead zones form when fertilizer and other pollutants high in nitrogen and phosphorus are washed by rain into a lake or bay. The compounds feed an explosive growth of algae, which, in turn, die and rot. Bacteria devouring such decaying biomass consume oxygen, suffocating marine life, which also fall to the bottom of the body of water. Over time this rotting biomass is covered by layers of silt that is also washed into the lake or bay. Due to human activity the number of dead zones around the world has greatly increase in recent years. There are now about 405 dead zones in coastal waters worldwide affecting an area of about 95,000 square miles. The largest dead zone in the U.S., at the mouth of the Mississippi, covers more than 8,500 square miles, roughly the size of New Jersey. A dead zone also underlies much of the main-stem of Chesapeake Bay, each summer occupying about 40% of its area and up to 5% of its volume. Water with too little oxygen for fish and other active organisms is referred to as “hypoxic.”  Earth’s largest dead zone, in the Baltic Sea, experiences hypoxia year-round. Chesapeake Bay experiences seasonal, summertime hypoxia through much of its main channel. The accumulation of dead algae and dead aquatic life progressively covered by layers of silt over thousands of years is the primary generator of petroleum on the planet.

A dramatic example of the rapid generation of an algae bloom that could create a dead zone occurred at the 2008 Beijing summer Olympics. The lake on which canoe races were to take place became filled with algae over the course of a few days. The algae covered 13,000 square kilometers of water. Workers pulled out over 100,000 tons of algae. Some of the algae collected is shown in Figure 8. Algae blooms are common in heavily polluted China, particularly in freshwater lakes. They are mostly caused by the discharge of untreated sewage containing high concentrations of nitrogen, a main ingredient in detergents and fertilizers.

            Figure 8. Chinese workers use a conveyor belt to remove green algae

Technology has been developed to convert algae and other biomass into petroleum, diesel fuel and other liquid fuels without waiting thousands of years. Research is progressing to develop this technology on an industrial scale to displace fossil fuels. However, even if this technology is successful, it will not reduce the amount of CO₂ in the atmosphere, only reduce its rate of increase. This will not be enough to stabilize earth’s climate.

While no one wishes to see their pristine ecosystem turned into a dead zone, it may be possible to create designated dead zones in which the conditions for the accumulation of plant and animal matter can be accelerated. The goal would be to keep such deposits buried and not extracted for fuel.

One potential area for intentionally creating a dead zone is in the Gulf of Mexico. This area, particularly around Louisiana has lost hundreds of square miles of coastal land to the sea over the last several decades, exposing cities like New Orleans that were previously protected from storms and hurricanes in the Gulf by miles of forests and swamps. If an undersea wall could be built in an area in which land is desired to be recovered, part of the flow of the Mississippi River, particularly during floods, could be diverted into this area where it would deposit silt and nutrients and produce algae blooms before flowing into the Gulf of Mexico.

Producing new oil shale

The mechanism by which oil shale is produced is fundamentally different than that for producing petroleum. Oil shale is produced when organisms in the open ocean die and sink to the bottom. Videos of the ocean depths taken by deep sea submersibles show a continuous rain of organic particles sinking to the bottom of the ocean. These particles include carbonate skeletons of sea creatures and organic hydrocarbon material. These are mixed and compacted by the ocean depths creating the carbonaceous rock infused with oil known as oil shale.

There are large areas of the oceans that are essentially biological deserts. It has been found that these areas are deficient in iron. Experiments have been performed that demonstrated that small quantities of iron filings (about 3 kg/km² or about 20 pounds/mile² ) spread out over the ocean surface could create photo plankton blooms over huge areas essentially overnight. These photo plankton are the basis of the food chain, and they suck up CO₂ from the atmosphere. It has been argued that much of the carbon generated in this way would eventually be recirculated by the oceans and only a small percentage would become permanently sequestered at the bottom of the ocean. However, over time a small percentage can add up to a very large amount when large currently unproductive areas of the ocean are involved.

In addition, encouraging the growth of photo plankton can have other beneficial side effects. Photo plankton serve as a food source for zooplankton, which serve as a food source for successively larger sea creatures. By building artificial floating reefs in these open oceans fish would be encouraged to breed and large commercial fisheries could be developed.

Creating limestone

While carbon sequestration by injection of liquid CO₂ into deep wells could be dangerous if the CO₂ finds a way to escape, it may be possible to inject liquid CO₂ into rock formations in which the CO₂ interacts with the rock to form stable carbonate minerals, such as limestone, so that the carbon is stably confined and cannot escape. This may be possible in basalt rock formations that comprise about 65% of the earth’s crust. In particular, liquid CO could be injected into undersea basalt caverns, mix with the sea water and interact with the rock. There are about 30,000 square miles of honeycombed basalt formations in about 9000 feet of water off the west coast of the United States. Liquid CO₂ could be pumped into these cavities, be converted to limestone and permanently locked away. An experiment to test this concept is being conducted in Iceland. Here the liquid CO₂ will first be mixed and dissolved into sea water before it is pumped into undersea rock formations.

These and other methods of carbon sequestration, as well as reduction in the production of greenhouse gases, could enable humans to gradually gain control over the amount of CO₂ in the atmosphere and stabilize the earth’s climate. This will not occur soon enough to prevent the earth’s climate from reaching a tipping point, but could help us gradually work our way out of the situation we have created. Stabilizing earth’s climate will require a degree of cooperation among nations unprecedented in human history, but not to work to stabilize earth’s climate will certainly result in widespread ecological changes, famine and massive population displacements.