Climate change will result in the transformation of much of the world over the next few hundred years. But many of these changes won’t be physical ones, they will be changes to the human-created infrastructure and social systems of the world. Even if the conditions of the physical world remain well within the limits of human survival, the world will no doubt seem a very different place to people.

In the article below I examine some of the most likely, and most important (to humans) effects of climate change. But most specifically those that affect the social-systems and infrastructure of the world. Effects such as the likely-hood of large (perhaps global) resource-based wars, agricultural-failure/diminishing-productivity, large-scale migrations, outbreaks of disease/pandemics, and the desertification/non-livability of many currently inhabited areas of the globe.

Regardless of any policy changes that governments may enact, or any potential drops in greenhouse-gas emissions caused by other factors, climate change will still continue. Even if all greenhouse-gas emissions were completely ceased today, the effects would still continue for quite some time — thanks to what is already in the atmosphere, and whatever feedback loops have already become active. And there is strong evidence that many feedback loops, have in fact, started kicking in. Feedback loops such as: methane release from melting permafrost, methane-clathrate release from the sea-floor, growing numbers of forest fires, desertification, rainforest drying, increasing levels of atmospheric-moisture, and a lessening of the albedo-effect in the arctic as the sea-ice disappears.

At current rates of greenhouse-gas emission (and not even factoring in feedback loops), the average world temperature is on track to rise by 11 degrees Fahrenheit by 2100. In all likely-hood though, the temperature will probably end-up higher than that — as global emissions of greenhouse-gases will very likely continue rising into the foreseeable future as the ‘undeveloped’ world continues industrializing.

Modern civilization, and its massive number of infrastructure-dependent people, is almost entirely reliant upon the delicate infrastructure of the modern world for its survival. If any significant damage were to occur to this delicately-balanced infrastructure, large numbers of people would starve, be forced to migrate, or be motivated to war — while, in the process, becoming increasingly susceptible to disease and illness.

Large Wars, Destabilization, Eroding Social Structures, and Rising Levels Of Violence

Large scale war or civil collapse is almost an inevitability in regions facing very scarce freshwater resources, very limited agricultural-land/productivity, and large-populations. And these are exactly the conditions that many regions of the world are expected to face as climate change intensifies.

Climate change is very likely to become a powerful catalyst for the many simmering conflicts and rivalries that are currently present in the world. And also for the destabilization of many governments and economies, in some cases leading to full on civil war and social collapse.

The two main drivers for this, a large drop in agricultural productivity, and freshwater scarcity in many regions, are predicted with even mild levels of warming. And with higher levels of warming, the effects on food and water availability will be much more severe.

It’s important to note that these conditions won’t happen in a vacuum — they will coincide with the increasing scarcity of industrially necessary resources, such as agricultural-fertilizers and forestry-products, and also with increasing rates of desertification and soil-salinization. In such conditions, there will be no options for many governments/people except to go to war for resources, migrate if possible, or die.

Many analysts are currently of the opinion, though, that inter-state wars are an unlikely result of climate change. And that it is much more likely that smaller groups will emerge from the destabilized governments and populations to become the main drivers of future conflicts. Maybe something similar to the currently active, decentralized Islamist movement, Boko Haram.

In a recently released report from The Military Advisory Board (a panel of retired US generals and admirals), the prediction is made that climate change will have very significant implications for the United States, and the world in general. It will essentially be a “threat multiplier” — as they word it — causing conflict in already volatile regions to flare up.

And Britain’s Foreign Secretary Margaret Beckett continues along the same line of thought, saying that, “An unstable climate will exacerbate some of the core drivers of conflict, such as migratory pressures and competition for resources.”

“…has the potential to challenge regional and even national identities. Armed conflict between nations over resources, such as the Nile and its tributaries, is likely…” and also “Perhaps the most worrisome problems associated with rising temperatures and sea levels are from large-scale migrations of people — both inside nations and across existing national borders.”

As a side note, recent research based on paleoclimate data was able to establish a very clear link between the “long-term fluctuations of war frequency and population changes” and climate changes in preindustrial times.

The scale and rapid nature of modern climate change, and the currently enormous world-population levels, are a large anomaly in the paleo record though, it’s hard to say exactly what will happen and on what scale. But regional conflict, increasing levels of violence, and crumbling social-structures in many parts of the world seem an inevitability.

Large-Scale Migration

The displacement, and migration, of very large-numbers of people, will be one of the most significant effects that climate change will have on humans. Often times these displaced populations will have no where to go except to regions that are already densely inhabited. Many of which, will likely already be having trouble supporting their own population.

These future displacements will be driven by two primary causes: an increasing number of very powerful storm and extreme weather events, and the somewhat slower processes of desertification and sea-level rise. As it stands now, the majority of the world’s most densely packed cities are located in coastal areas. These populations will either have to move, or to erect enormous and expensive barriers to hold back the sea (at best temporarily) and storm-surge. To a lesser degree (probably), war and conflict will also be a contributing factor to migration.

Desertification is already causing changes in the social environment of certain areas of the African Sahel. Agriculture, livestock, and over-population have been the primary reasons that this previously stable dry-land ecosystem has been turning into desert. At the same time as these physical changes have been occurring, social-destabilization and migration also have been, leading to food-insecurity, disease outbreaks, and increasing levels of cultural extremism.

Throughout history, natural disasters and environmental change have often been the cause of migration, and the war/raiding that is sometimes associated with it. The “Sea Peoples” of the late Bronze Age collapse (Mycenaean Palatial civilization collapse) function as a good example. They were essentially a loose confederacy of seafaring raiders from southern Europe that raided and invaded Egypt, Anatolia, Syria, Canaan, and Cyprus — and were responsible for the destruction of multiple civilizations, such as the Hittite Empire. It’s been well noted that they weren’t simply a military group, their ships housed women and children also. Very interestingly, recent research has shown that the date at which they are first mentioned in Egyptian writings nearly coincides with a very large eruption of the Santorini volcano (estimated between 1660-1613 BC). “The eruption and its aftermath (fires, tsunami, weather changes and famines) would have had wide-ranging effects across the Mediterranean, the Levant and particularly Greece, and could have provided the impetus for invasions of other regions of the Mediterranean.”

In more recent times, large-migrations have also occurred as a result of extreme weather and natural disasters. According to the Internal Displacement Monitoring Center, “more than 42 million people were displaced in Asia and the Pacific during 2010 and 2011, more than twice the population of Sri Lanka. This figure includes those displaced by storms, floods, and heat and cold waves. Still others were displaced by drought and sea-level rise. Most of those compelled to leave their homes eventually returned when conditions improved, but an undetermined number became migrants, usually within their country, but also across national borders.”

As climate change continues intensifying, these numbers will increase, and many times it won’t be possible for people to return to their previous homes.

Disease, Epidemics, and Malnutrition

(Author’s note: For more details on the painting above, and related topics, see: The Triumph Of Death — Pieter Bruegel The Elder, The Black Death, Two Monkeys, & The Eighty Years War)

One of the least predictable, but potentially most devastating, effects of climate change will the increasing levels of infectious disease, malnutrition, and the increased possibility of pandemics.

It’s been predicted that malnutrition, especially amongst children, will rise significantly because of decreased agricultural output, and weakened social and governmental structures. Malnutrition — on its own, but especially when combined with scarce/dirty water, stronger natural disasters, increased levels of air-pollution (caused by higher temperatures), the spread of disease-vectors, and mass migration — will result in enormous health problems in many of the poorer parts of the world.

As temperatures rise, so do smog-levels. Much higher levels of smog, and the pollutants that they consist of (ground-level ozone, carbon monoxide, sulfur dioxide, and nitrogen dioxide) are expected to become the norm throughout many of the warmer urbanized regions of the world. Very likely resulting in an associated uptick in the diseases/conditions caused by these pollutants: cardiovascular disease, decreased immune system function, emphysema, asthma, and decreased athletic/physical performance. Smog also greatly limits the efficiency of photosynthesis — resulting in the disappearance of many species of plants in the immediate area, and decreasing agricultural-yields.

And for those doubting how deadly smog can be, it can kill in the short-term, not just over longer time-frames, as the Great Smog of 1952 in London demonstrated. “The Great Smog of 1952 darkened the streets of London and killed approximately 4,000 people in the short time of 4 days (a further 8,000 died from its effects in the following weeks and months). Initially a flu epidemic was blamed for the loss of life.”

Many infectious diseases are expected to greatly increase their range as the world warms, primarily due to the spread of common disease-vectors, such as mosquitos and ticks. Malaria in particular is expected to become a huge problem throughout much of the world. Currently, malaria kills about 300,000 children every year — which is already a lot, but that number is expected to grow exponentially with climate change. In particular, mosquitos and malaria are a significant problem in many agricultural areas that rely on irrigation, which will possibly become a necessity in many parts of the world with increasing aridity.

As a 2006 study published in the Proceedings of the National Academy of Sciences notes, “Though many infectious diseases are affected by changes in climate, vector-borne diseases, such as malaria, dengue fever and leishmaniasis, present the strongest causal relationship. Malaria in particular, which kills approximately 300,000 children annually, poses the most imminent threat.”

Large migrations and increasing population densities — two very likely effects of climate change — also greatly facilitate the spread of infectious disease. Many of the largest pandemics in human-history have been as a result of spreading human-populations.

Agricultural Failure and Diminishing Productivity

Climate change is expected to have a large and generally very negative effect upon agriculture. And particularly upon industrial-agriculture, with its reliance on imported fertilizers, pesticides, and long-distance transportation/refrigeration. In spite of all the technology that is currently in use, weather and soil-quality are still the primary determinants of crop-yield. As these conditions deteriorate, so will crop-yields. There is expected to be some variability in this regard, as increasing temperatures in northern latitudes will improve yields somewhat in those regions, while making agriculture in some previously-productive regions impossible. The trend is certainly towards lower-yields though.

Specifically, the effects of rising temperatures, higher carbon dioxide levels, decreasing glacial run-off, changes in precipitation patterns, and increasing insect-populations, have been recognized as the most likely to exert considerable influence on agriculture.

An important thing to note though is that many countries are reliant upon imports to feed their population — without global-trade many countries simply wouldn’t have the food to keep everyone fed. The unreliability of such arrangements was demonstrated after the 2010 Russian Wildfires, when Russia lost 25% of their wheat-harvest, and subsequently banned exports of the grain. Russia is one of the largest wheat exporters in the world (11% of global-exports), many countries import a large-amount of wheat from them. After the ban went into effect global wheat-prices soared to a two-year high, from $4.55 to $7.86.

Most of the studies that have been done on the effects that climate change will have on agriculture have not even factored in extreme weather events such as the Russian wildfires, but even without disasters crop-yields are expected to drop significantly. With them, the decrease could be very severe.

A recently published study in the journal Science, found, that due to climate change, “southern Africa could lose more than 30% of its main crop, maize, by 2030. In South Asia losses of many regional staples, such as rice, millet and maize could top 10%.”

The Intergovernmental Panel on Climate Change’s Third Assessment Report concluded, “that the poorest countries would be hardest hit, with reductions in crop-yields in most tropical and sub-tropical regions due to decreased water availability, and new or changed insect-pest incidence. In Africa and Latin America many rainfed crops are near their maximum temperature-tolerance, so that yields are likely to fall sharply for even small climate changes; falls in agricultural-productivity of up to 30% over the 21st-century are projected. Marine-life and the fishing-industry will also be severely affected in some places.”

Desertification, Water-Scarcity, And Deforestation

As the climate warms, the patterns of global-rainfall, evaporation, snow, and stream-flow, change greatly. This has important implications for many people, greatly impacting their access to freshwater. “Freshwater resources are highly sensitive to variations in weather and climate. Climate change is projected to affect water-availability. In areas where the amount of water in rivers and streams depends on snow melting, warmer-temperatures increase the fraction of precipitation falling as rain rather than as snow, causing the annual spring peak in water-runoff to occur earlier in the year. This can lead to an increased likelihood of winter-flooding and reduced late-summer river flows. Rising sea-levels cause saltwater to enter into fresh underground water and freshwater streams. This reduces the amount of freshwater available for drinking and farming. Warmer waterstemperatures also affect water-quality and accelerate water-pollution.”

Desertification is going to be a much greater problem though, one that encompasses the water-scarcity issue. Water-resources are very closely entwined with climate, and with the land-degradation that follows deforestation and agriculture. With the climate already warming, and becoming more arid in many regions, the continued and increasing levels of deforestation and agricultural use will transform many regions into deserts rather quickly.

In particular, many areas of Africa that are currently agriculturally-productive are expected to essentially become deserts. In many of the drier regions of Central and South America climate change is expected to rapidly lead to the salinization and desertification of large portions of agricultural-land. And in Southern Europe drought is expected to become much more common, coinciding with significantly-higher temperatures, and greatly lowering crop-productivity.

The south western region of the United States is also worth mentioning, it’s been predicted that the region will be in a state of permanent drought by 2050, with levels of aridity comparable to the 1930s Dust Bowl stretching from Kansas to California. When you also consider that the groundwater-reserves that allow those regions to be populated and to feature agriculture are fast being depleted, the future of agriculture in the region seems very questionable.

Deforestation rates all over the world are also likely to greatly increase. Partly as a result of increasing-demand for forestry-products and diminishing availability, and partly as a result of forest fires, aridification, insect plagues, and disease. Which will in itself greatly contribute to worsening climate change, desertification, and decreasing agricultural-productivity.

Source: Wikipedia, German Advisory Council on Global Change, and IPCC

Image Credits: Desert, Plague, Kuwait, Berlin, and Refugee Camp via Wikimedia Commons, Corn, via Flickr CC