In the previous post we explored the extreme stratification of wealth and power among the world's humans, so our next task is to evaluate the state of human health (and consequently lifespan) across this spectrum. Like wealth inequality, those of us living in the First World are largely unconscious of just how the majority of the world lives. We may assume that our general state of health and sanitation is the norm, and that deficiencies are the outlier. So let us turn to the data to evaluate the validity of this assumption.
For most of human existence (prehistory and history up to the industrial revolution), humans lived on average 30-40 years. Of course, this does not mean that humans could not or did not commonly live to much older ages, just that when we average all of the ages of death together it ends up being in the 30's. This is largely attributable to high levels of childhood mortality, with only about 60% of live births surviving to age 15 in traditional hunter-gatherer societies. This is actually a comparatively high survival rate, with many mammal species maintaining only a 40% survival rate to reproductive age. We might speculate that even the most primitive societies derive some survival benefit from the use of simple tools and learned techniques that provide an advantage over species without these abilities.
Research shows that humans have always had the potential to live approximately 7 decades, and it would be "normal" to have some members of a population reaching this age regardless of the time period. However, it is undeniable that modern sanitation, water purification, food production and transport, and medical practices have decreased the death rate for children immensely while also increasing the number of people living to older ages. In the developed world more than 99% of live births now survive to age 15, providing a huge boost to the "average" life expectancy.
Like wealth distribution, the benefits of improved health and life expectancy vary greatly among the world's population. At the risk of this post becoming a "map overload", this global view is probably the best way to spot correlating factors and areas facing the greatest challenges in the area of human health. First, a look at life expectancy by country:
Across the developed world, in the wealthiest countries, life expectancy is generally at or above the seven decade level. Across the poorer countries (particularly in Africa and parts of Asia and South America), life expectancy is much lower and in some cases is actually no higher than it was prior to the industrial revolution. As with all complex outcomes, there are obviously many factors that play a part in these life expectancy statistics; however, there are several important correlations that we should examine to help us understand these relationships. Intuitively we can understand that modern medical care plays a huge role in expanding lifespan and improving overall health, but there are several other factors that play an even more substantial role and are more fundamental to maintaining even base levels of health and longevity.
The first factor to examine is the most basic to life: access to clean drinking water. Humans will perish quickly without water, and unsanitary water is one of the easiest ways to transmit deadly diseases that can have a huge impact on health outcomes. The pattern of access to clean drinking water is similar to the pattern of life expectancy, with many equatorial and especially African countries suffering the greatest lack of access. In some cases well over half of the population lacks access to clean water.
After access to clean water, access to stable supplies of nourishing food is the next most important factor in human health. Again, the pattern of malnutrition around the globe mirrors our other health factors. The same parts of the world experiencing the shortest lifespans also suffer from the greatest lack of access to clean water and the greatest rates of undernourishment.
Finally, without crossing too far into our next category of data (environmental conditions), it is worthwhile to show a a correlation between the geographic distribution of these health factors and the incidence of drought. We can see that significant parts of the world experience drought disasters, and that the extent of these droughts largely matches with the areas of poor water access, nutrition, and life expectancy with a few exceptions. Highly industrialized countries such as the United States, Canada, Australia, southern Europe, and to some extent China seem to avoid some of the poor health indicators despite being associated with a prevalence of drought disasters.
The data shows us that for large parts of the world, the technology of modern civilization has increased lifespans and decreased mortality. There are, however, still examples of places where these advances have failed to substantially improve the human health situation. There is a strong correlation between drought conditions, access to clean water, population nutritional status, and health outcomes like life expectancy. The places that are already experiencing pressure from these combined factors will be an important area of reflection in our projection of future conditions, as they provide us with points of comparison to our own experiences of enhanced health and lifespan within industrial civilization. In a world without modern methods of water purification, food production, and medical care made possible by industrial civilization, the demographics of global health and lifespan might more closely resemble those we currently see in the most health-deprived parts of the world such as central Africa and parts of Asia.
Perhaps the most important overarching data point for us to carry forward in our analysis is this graph of the long term trend:
From this perspective, much like our earlier perspective on population growth, we can see that the current explosion in life expectancy and health is purely a product of the industrial revolution and the incredible advances in technology enabled by our expanded energy consumption. Improved sanitation, water transport, food production and distribution, and medical technology have all contributed to a massive improvement in human health. The ability to burn fossil fuels for energy to support industrial civilization is the sole reason for this departure from the norm of the 30 year human life expectancy. Without getting too far ahead of ourselves, we can probably make the assumption that in the absence of our current levels of energy consumption, technology, and industry, basic measures of human health would eventually revert back to their mean and we would once again see the 60% survivability to adulthood and average life expectancy in the 30's that was historically typical for humans.
Of course, the survivability of all species, including humans, is dependent upon maintaining suitable habitat. Species evolve as part of an ecosystem, which will naturally experience change due to climate, geology, species competition, and any number of other factors that have shaped environments since time immemorial. At our current moment in time, however, the activities of a single species are exerting an influence on the natural environment in ways never before experienced.
Industrial civilization is literally changing the face of our planet in profound ways. In order to support the massive explosion in human population, cities and their associated infrastructure expand to cover ever greater land area and agricultural production must constantly grow through greater mechanization, centralization, and scale. Industrial agriculture and urbanization have spread across the globe, and as a consequence of these intensive land uses the earth's soils have degraded and eroded to a fraction of their original productive capacity. Only comparatively small areas on each continent currently maintain stable, non-degraded soils.
Part of the strategy for dealing with degraded soils and lost productivity is to increase the application of fertilizers. To keep pace with rapid population expansion, agricultural production must increase year after year on soils that are more and more degraded, resulting in a steady increase in the application of even more fertilizers. It should be noted that commercial fertilizers are produced with the use of large amounts of fossil fuel energy, as well as natural gas as a direct input. They are fossil fuel products in a very literal sense.
Another strategy for extracting greater efficiency from declining soil quality is to reduce the loss of food product from drought, pests, and weed competition. Genetic modification has allowed industrial agriculture to create new varieties of crops never before seen by nature that grow faster, more efficiently, and can resist massive applications of poisons that would quickly kill the original, naturally evolved plant species.
Equipped with massive fields owned or controlled by contract relationships, heavy farm machinery powered by fossil fuels, genetically modified crops, and large quantities of pesticides, herbicides, and fertilizers produced directly and indirectly by fossil fuels, a new model of food production has come to dominate the world. It is possible to witness this model at work with only a quick day trip from most metropolitan areas, to the "countryside" where food production takes place.
Each year, huge diesel powered tractors break open the earth. The soil itself no longer contains the nutrients essential to grow crops because these fields have been broken open year after year and planted with the same crops, which extract the same nutrients. More diesel equipment passes over the field, spreading fossil fuel fertilizer across the dead soil to "enrich" it with the ingredients necessary to support life. Several more passes with fossil fuel powered equipment plow and till the soil, set up neat rows, and spread genetically engineered seeds. Water diverted from rivers and streams miles away is periodically flooded into the field. Occasionally, more large trucks pass over the field spraying pesticides and herbicides liberally on the crops (which are immune to their effects due to the manipulation of their genes). At some point, aircraft fly back and forth over the field dropping poison from the sky to ensure the crops face no natural competition. Finally, harvest comes and more massive machines powered by oil products strip the crops, carry them over roads to plants where they are processed by machines, packaged, and shipped long distances over more roads and even across oceans to their final destination, where people drive in their gas powered cars to purchase them.
The point of this lengthy exposition is to point out the extent to which high technology and fossil fuel energy are inseparable from modern civilization's food production process. Agriculture consumes about 3% of the worlds total energy but produces nearly 20% of greenhouse gas emissions, in large part because of the dependence on oil products to power equipment. There is currently very little in the food production process that can reasonably be converted from oil to renewable energy sources like solar or wind.
In addition to the need for increased productivity of existing agricultural lands, population growth also demands the continual addition of new productive capacity in the form of farmland. The result of this expansion, as well as the drive for wood and wood products, is deforestation. Since the advent of civilization and human population expansion, the world has lost approximately half of its original forest cover. Of this, only a small fraction exists as large undisturbed ecosystems.
Other species heavily dependent on forests and other natural habitats are also experiencing the impacts of human encroachment. The massive diversity of earth's animal life lives in the same forests and fields being converted to crops and suburbs, drinking the water and eating the food that comes in contact with the pesticides, herbicides, and fertilizers of industrial agriculture. For many species, the pressures are too great and are happening too fast for meaningful adaptation or evolution. The current rate of animal extinction is approximately 1,000 times higher than natural background levels, with dozens of species going extinct every day. This is the worst rate of die-offs since the extinction of the dinosaurs 65 million years ago, leading some scientists to identify this as a period of "mass extinction." This is only the 6th mass extinction event to have occurred in the history of the world, and the only one ever caused by the actions of a single animal species.
There are many other areas of environmental impact that have not even been mentioned yet, but it would take pages and pages over many posts to explore and innumerate them all. We have not discussed the waste products of industrial production, from landfills to chemical byproducts. We could dedicate paragraphs to the Great Pacific Garbage Patch, the plastic soup filling up vast expanses of the largest ocean. There is much more that could be said about these impacts and the truly horrifying transformations taking place in the natural environment as a consequence of civilization, but we have to carry on with our analysis. And there is one final environmental factor to discuss that is of the most critical importance to everyone and everything living on the planet today.
No discussion of the state of the environment would be complete without an analysis of human carbon dioxide emissions and human-caused climate change. If civilization's primary inputs are fossil fuels, then one of the primary outputs is carbon dioxide. Since the industrial revolution, the amount of carbon dioxide in the atmosphere has continually increased as a result of human activity. The rapidity and scale of the rise in CO2 is truly unprecedented in the history of the planet- in the past it might have taken tens of thousands of years for levels to rise as much as they have in the past 200 years.
Current atmospheric CO2 measurements are now exceeding 400 parts per million, a level not seen since the Pliocene era 3.6 million years ago. At that time, global average temperatures were about 8 degrees Celsius warmer than today, the arctic tundra was lush forest, and sea levels were about 20 meters higher. So why have we not seen warming and dramatic changes yet that look more like the Pliocene? Because the increase in CO2 emissions has happened so rapidly that the warming effects are still taking hold. There is approximately a 10 year lag in the warming effect of CO2, so today we are just feeling the warming of emissions that happened in 2006. It is true that atmospheric CO2 levels are cyclical, but our current levels are far outside of any natural cycle seen in the past.
Last year, the nations of the world gathered to discuss an agreement on climate change at COP21 in Paris. Recognizing the potentially catastrophic consequences of exceeding certain thresholds in temperature change, the participants agreed to a non-binding target of holding warming to 1.5 degrees Celsius above pre-industrial levels. Currently, temperature anomalies are already more than 0.8 degrees above this baseline. It is highly likely that a certain amount of additional warming is already "baked-in" based on current CO2 levels (not even accounting for additional warming factors that may come into play)- but we will discuss this more in our projection of future conditions.
The impacts of this warming can be seen in the form of increasing sea level rise (3.4 mm per year), dramatically decreasing arctic sea ice, melting land glaciers, and shifts in local and global weather patterns (droughts, hotter summers, colder winters, more powerful storms). We can expect that if/when warming continues, the impact of these changes will become greater.
This rounds out our discussion of the current conditions of our planet. Obviously there are many other important subject areas we could include and much greater depth could be dedicated to each of these areas, but this core understanding should be considered the minimum necessary to be comprehensive in our planning process.
In the next posts, we will proceed to projecting the future conditions of the planet.