Hans-Peter Plag
Nevada Geodetic Laboratory, University of Nevada, Reno, USA
Presented on April 18, 2008 at Stony Brook University, Stony Brook, NY, USA; see the EarthStock page.
Copyright 2008, Hans-Peter Plag
Abstract ... \ECO \BCO 2
This presentation has the following main parts:
Hans-Peter Plag
Nevada Geodetic Laboratory, University of Nevada, Reno, USA
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The theme of EarthStock is "Sustainability - the Future is Now", which in its seemingly simple wording is a very complex and insight full theme: considering the complexity of human societies and our planet, the present action determine the future, and only if we realize the aspect we want to see in the future now, there will be a future as we envision it. The theme also involves "sustainability" and I will try to show you that in the interaction of the sophisticated beings we humans are and the complex system our planet is "sustainability" is not a given characteristics. In fact, in human history "sustainability" is a rather young concept, which has come to popularity over the last few decades only. It comes along in various shades, with the most prominent, and the one likely to survive being "Sustainable Development". \ECO \EOB \SOB \NUM 2 \BCO 2
Sustainability is a characteristic of a process or state that can be maintained at a certain level indefinitely (Wikipedia). In a real world, this descriptive definition is not possible to meet and sustainability is not a characteristics of a steady-state processes but rather a characteristics that will change over time for any process.
Applied to human societies, sustainability reaches into all fields of society and our interaction with the planet, which is often depicted by the three main fields of economics, social, and the environment. In each of these fields, we can make many choice that lead away from a sustainable development, or choices that bring us closer to it. \ECO \EOB \SOB \NUM 3 \BCO 2
As defined in the report on ``Our Common Future'' prepared by the World Commission on Environment and Development, the Brundtland Commission, in 1987, Sustainable Development is to meet the needs of the present without compromising the ability of future generations to meet their own needs (..., 1987). By striving for sustainable development, we do not follow a natural law or try to be compliant to a given principle. Neither do we follow just a political concept, as sustainable development it is often described. In its broadest sense, sustainable development only makes sense as an ethical principle, as a basis and guidance for the choices we have to make. Adhering to the principle, we make the choice to meet our needs, not just the material ones, without compromising the ability of our kids to meet their own needs, not even knowing what their needs will be. This principle applies not only to the needs of future generations: adhering to the principle, we make the choice to meet our needs without compromising the ability of our contemporaries to meet their needs. In this sense, again the future is now. \ECO \EOB \SOB \NUM 3 \SUB 2 \BCO 2
Any process will over time be closer or further away from sustainability, and a process may or may not produce adjacent states that diminish or increase the sustainability potential of the system we are talking about. Understanding this inherent dynamic nature of sustainability, we realize the need to constantly assess our actions with respect to their contribution to sustainability.
For the operationalization of the ethical and political concept of sustainable development, we need a quantitative definition and we need a metric to measure progress towards sustainability. Likewise, it requires the means to predict consequences of action, so that we can make informed decisions. We can introduce a quantitative definition based on the life expectancy of the system and trajectories of certain factors in the system. \ECO \EOB \SOB \NUM 3 \SUB 3 \BCO 2
Thus, it must be clear to everybody that once we have made this ethical choice to strive for sustainablity, once we decided to make sustainable development the underlying principle for our economic and social activities, then a successful quest requires solid scientific input: living on a dynamic, evolving, complex planet, a planet, as pointed out by Lovelock in his Gaja hypothesis, in a homestatic equilibrium, with a physiology comparable in its complexity to that of a human body, living on a planet we share with a rich biosphere with many biological components and ecological conditions contributing to the state and dynamics of the planet, it is extremely challenging not to compromise the ability of fellow people and future generations to meet their needs. \ECO \EOB \SOB \NUM 4 \BCO 2
Fundamental Questions include:
Compared to all the other planets we know, ours is a very special one. While Mars and Venus are at the end stage of planetary development in a more or less dead stage of stable equilibrium, ours is somewhere in the middle and highly dynamical. Being in the narrow zone with respect to the sun where water can exist in its fluid phase, the global water cycle facilitates a number of other transport cycles. As Lovelock describes it in his book "Gaja", seen from space Earth emits light with a spectrum indicating a dynamic, a homestatic equilibrium, which can only be maintained by active life. \ECO \EOB \SOB \NUM 6 \SUB 1 \BCO 2
Over its existence, Earth has developed a rich biosphere with a large and still unknown number of species, which occupies more than ... orders of magnitudes from small microbes to whales, and which has adopted to nearly all environments on Earth from ice to submarine volcanoes. Microbes, reptiles, insects, birds, mammals, together form a rich variety of ecosystems that turn Earth's surface into a highly variable mosaic of small but interconnected patches depending on available energy, nutrients and links to other ecosystems. \ECO \EOB \SOB \NUM 7 \SUB 1 \BCO 2
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Humanity has grown in number tremendously. 10,000 years ago, at the end of the last ice age, we were an estimated one million. At the time of the Roman Empire we had grown to some two hundred million. At this size, we were already able to change Earth's surface significantly and, for example, deforest a large part of the Mediterranean coast hills and adjacent land areas. Today, with more 6 billion, we are more than thirty times as powerful, able to alter a large fraction of Earth's surface substantially. \ECO \EOB \SOB \NUM 12 \SUB 2 \BCO 2
Humanity has grown in number tremendously. 10,000 years ago, at the end of the last ice age, we were an estimated one million. At the time of the Roman Empire we had grown to some two hundred million. At this size, we were already able to change Earth's surface significantly and, for example, deforest a large part of the Mediterranean coast hills and adjacent land areas. Today, with more 6 billion, we are more than thirty times as powerful, able to alter a large fraction of Earth's surface substantially.
And we still continue to grow. Although in some continents population growth is zero or even slightly negative, in other continents population is growing at a high rate. \ECO \EOB \SOB \NUM 12 \SUB 3 \BCO 2
And Humanity is not distributed evenly over Earth's surface. While in some areas population density is as low as 1 person per square kilometer, in other areas density exceeds already today 500 people per square kilometer. Often, these high density is found in regions that already today cannot sustain the population with water, food, and other resources. \ECO \EOB \SOB \NUM 12 \SUB 4 \BCO 2
And Humanity is not distributed evenly over Earth's surface. While in some areas population density is as low as 1 person per square kilometer, in other areas density exceeds already today 500 people per square kilometer. Often, these high density is found in regions that already today cannot sustain the population with water, food, and other resources.
Expressing population grows in population doubling times helps us understanding the full dimension of the challenge humanity faces. In some countries, doubling times are as low as 15 years. It must be obvious to everybody that combining the low doubling times with centers of high population density, as is the case in several "hot-spot" areas, will lead inevitably to an unsustainable situation in the near future, where the population in these hot-spots face only two choices: either to die or to migrate to regions with less people and more resources. The tension and conflicts arising from this rapidly developing social disaster are a threat to the stability and sustainability of our global civilization. \ECO \EOB \SOB \NUM 13 \SUB 1 \BCO 2
And humanity has grown in activity. An impressive example is deforestation. Once upon a time, Earth's surface to a large extent was covered by forrests, dense forests in many areas that it was difficult for humans to actually dwell in them. A hypothethese states that, for example, four thousand years ago, the British Isles were covered with a forrest so dense that humans moved along the coasts to the North but did not explore the interior. The map shows the extent of the original forrests. \ECO \EOB \SOB \NUM 13 \SUB 2 \BCO 2
And humanity has grown in activity. An impressive example is deforestation. Once upon a time, Earth's surface to a large extent was covered by forrests, dense forests in many areas that it was difficult for humans to actually dwell in them. A hypothethese states that, for example, four thousand years ago, the British Isles were covered with a forrest so dense that humans moved alongun the coasts to the North but did not explore the interior. The map shows the extent of the original forrests.
Today, large parts of the forrest are either gone and lost or heavily managed by humans. More than 50% of the forrest are gone (the brown areas in the lower left map) and the rest (shown in grey) are managed. Only 20% of the original forrest remain as what we call frontier forrest, and they are shown in green on the map. These frontier forrest are of very high value for the biosphere allowing for the undisturbed evolution of the ecosystems, but they are threatened by humanities pressure. \ECO \EOB \SOB \NUM 14 \SUB 1 \BCO 2
Another example is land use. We have created beautiful landscape, lucheous, tranquile landscape that please our soles and inspire our poems. Landscape that are rich ecosystems and refugees and island for many species. \ECO \EOB \SOB \NUM 14 \SUB 2 \BCO 2
Another example is land use. We have created beautiful landscape, lucheous, tranquile landscape that please our soles and inspire our poems. Landscape that are rich ecosystems and refugees and island for many species.
And we like to build our houses in managed and beautifully designed landscapes, although not all of us are able to have houses as big and beautiful as the one in the picture. But most of us like to have a small piece of land, even if it is just an urban frontyard, that we can put our very personal stamp on. We all feel like we need to impact our immediate environment. \ECO \EOB \SOB \NUM 14 \SUB 3 \BCO 2
Another example is land use. We have created beautiful landscape, lucheous, tranquile landscape that please our soles and inspire our poems. Landscape that are rich ecosystems and refugees and island for many species.
And we like to build our houses in managed and beautifully designed landscapes, although not all of us are able to have houses as big and beautiful as the one in the picture. But most of us like to have a small piece of land, even if it is just an urban frontyard, that we can put our very personal stamp on. We all feel like we need to impact our immediate environment.
But we also have impacted the environment negatively, changed it into devastated, ugly, industrial, monotoneous spaces deserted of rich ecosystems and void of thriving live. Most importantly, humanity has modified, permanently changed, or managed more than 50% of the ice-free surface of the Earth's surface. We have grown to a major power able of transforming the Earth's surface substantially. No other species has ever been in this position. \ECO \EOB \SOB \NUM 15 \SUB 1 \BCO 2
There are many examples that demonstrate the scale of our activities. One is the extent of croplands. Around 1700, croplands were basically limited to a few areas in Europe and Asia. \ECO \EOB \SOB \NUM 15 \SUB 2 \BCO 2
There are many examples that demonstrate the scale of our activities. One is the extent of croplands. Around 1700, croplands were basically limited to a few areas in Europe and Asia.
Today, cropland have not only increased in global extent to North and South America and Australia, but also intensity, as is illustrated by the transition from light gray to dark grey and black in many areas all over the world. \ECO \EOB \SOB \NUM 15 \SUB 3 \BCO 2
There are many examples that demonstrate the scale of our activities. One is the extent of croplands. Around 1700, croplands were basically limited to a few areas in Europe and Asia.
Today, cropland have not only increased in global extent to North and South America and Australia, but also intensity, as is illustrated by the transition from light gray to dark grey and black in many areas all over the world.
With the development of croplands and the extension of other acricultural use in to new areas, the need for irrigation increased, and today, irrigation is a major human intervention in the pre-human mass transport in the global water cycle. In many case, irrigation has had positive side effects, but there are also numerous examples where the diversion of water for irrigation purposes has led to environmental disasters, economic problems, and social conflicts.
With the increased activity of humanity we also see increased impact, side effects, so to say. Let us look at some of the very obvious examples. \ECO \EOB \SOB \NUM 16 \SUB 1 \BCO 2
In the 1960ies and in many decades before, the Aral Sea in the former Soviet Union was a desert terminal lake of considerable extent (see the Aral Sea) with thriving fishery and healthy twons and cities at its shores. . Russian engineers, who thought that this lake was an error of nature, decided that the water from the two rivers ... and ... feeding the Lake from the South and Noth-East could be diverted to irrigate the desert in order to plant cotton for export. \ECO \EOB \SOB \NUM 16 \SUB 2 \BCO 2
In the 1960ies and in many decades before, the Aral Sea in the former Soviet Union was a desert terminal lake of considerable extent (see the Aral Sea) with thriving fishery and healthy twons and cities at its shores. . Russian engineers, who thought that this lake was an error of nature, decided that the water from the two rivers ... and ... feeding the Lake from the South and Noth-East could be diverted to irrigate the desert in order to plant cotton for export.
In 1986, the Lake had already started to shrink. The breaking up of the Soviet Union accelerated this process because now the emerging countries Kasachstan, Usbekistan, and Turkmenistan without much coordination increased the diversion of water. \ECO \EOB \SOB \NUM 16 \SUB 3 \BCO 2
In the 1960ies and in many decades before, the Aral Sea in the former Soviet Union was a desert terminal lake of considerable extent (see the Aral Sea) with thriving fishery and healthy twons and cities at its shores. . Russian engineers, who thought that this lake was an error of nature, decided that the water from the two rivers ... and ... feeding the Lake from the South and Noth-East could be diverted to irrigate the desert in order to plant cotton for export.
In 1986, the Lake had already started to shrink. The breaking up of the Soviet Union accelerated this process because now the emerging countries Kasachstan, Usbekistan, and Turkmenistan without much coordination increased the diversion of water.
In 2008, the lake has shrunk to less than 25% of its original size, salinity has increased five-fold, fish died, and much of the former lake botton turned into dusty desert, freeing pesticide and nutrients stored in the lake during preceding decades. A major environmental developed rapidly with the economic basis for the adjacent settlements gone and the health of the population rapidly deteriorating due to the high air polution from the former lake bottom. \ECO \EOB \SOB \NUM 16 \SUB 4 \BCO 2
The lake is no longer navigable, ships are rotting as silent warning witnesses of the disaster. \ECO \EOB \SOB \NUM 16 \SUB 5 \BCO 2
The lake is no longer navigable, ships are rotting as silent warning witnesses of the disaster.
Animals utilize the sparse vegetation in the desert exposed by the retreating lake. \ECO \EOB \SOB \NUM 17 \SUB 1 \BCO 2
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