Does algae offer a solution to climate change violence?

by Dr. Mark Edwards

Aseries of recent studies confirm and begin to quantify the previously reported correlation between adverse climate change and conflict. Hot temperatures increase aggression by directly increasing feelings of hostility and magnify aggressive thoughts. Heat activates organisms and amplifies aggression, which is reflected in more reports of road rage and domestic violence when temperatures rise.

Climate change increases strain, reduces social control, weakens social support and fosters beliefs favorable to crime. Rising temperatures contribute to traits conducive to crime, increase certain opportunities for crime, and create social conflict.

Anyone who has experienced recent searing heat waves, extended drought, fierce storms and floods or wildfires understands why climate change often results in violent behaviors. Scientists have found that even small changes in temperature or rainfall correlated with a rise in individual acts of violence as well as group conflicts, riots and war.

Climate and violence science

A July 2013 meta-analysis published in Science examined 60 climate and violence studies from around the world, with data spanning hundreds of years. The study, led by Solomon Hsiang at the University of California, Berkeley, found a “substantial correlation between climate and conflict.” Hsiang and colleagues incorporated research on civilizations dating back as far as 10,000 B.C. and across all major world regions. The science of climate and violence as exploded recently and 78% of the studies included in the meta-analysis were been published since 2009.

The climate and conflict examples show an increase in domestic violence during droughts and a spike in assaults, rapes and murders during heat waves. They reported that police officers are also more likely to use force in higher temperatures. The researchers concluded that climate and violence are observed across time and across all major continents around the world.

Heat and Drought

When the Hsiang team examined evidence from 190 researchers, they determined that intergroup conflict increases 14% and interpersonal violence increases 4% for each standard deviation in climate variables. One standard deviation of temperature is about halfway between normal for average year and a really hot year.

The relationship found between climate variables and conflict outcomes are often very strong. The report anticipates rising temperatures will cause expanded conflicts, including ethnic clashes in Europe and civil wars in Africa. The scientists predict that current-warming patterns will significantly increase the occurrence of human conflict and wars by mid-century. They estimate that a 2 degrees C (3.6F) rise in global temperature could see personal crimes increase by 15%, and group conflicts rise by more than 50% in some regions.

Drought and Record Temperatures – U.S. and China

Tree rings and war

Can tree rings predict war? Several of the studies included in Science review examined articles on tree rings and wars. Good growing seasons with the right amount of moisture and temperatures that stayed within the narrow range for crops yield relatively wide growth rings. Low growth creates narrow growth rings from bad weather. When trees fail to grow, crops fail too, causing price spikes that lead to unrest, riots and rebellion.

A second team led by David Zhang examined temperature data and climate-driven economic variables during the “golden” and “dark” ages in Europe and the Northern Hemisphere during the past millennium. Their findings align with the China studies. The data indicated that climate change was the ultimate cause, and climate-driven economic downturn was the direct cause, of large-scale human crises in pre-industrial Europe and the Northern Hemisphere.

Cause of conflict

Correlation shows adverse climate change clearly relates to conflict but correlation studies do not indicate the cause of conflict. Three of the leading theories about why climate change causes conflict are food, economics and psychology:

  1. Food supply. Climate change depletes food supplies, driving up prices and access to food.
  2. Economic. Climate causes changes in economic conditions around the world, particularly in agrarian parts of the world.
  3. Psychology. Excessive heat causes people to be prone to aggression.

Food supply

Shifts in temperature and rainfall influence economic productivity and food prices. Bad weather causes crop failure, which leads to price spikes, fear, food riots and war.

The French Revolution in 1784 ignited due to escalating food prices. “Let them eat cake” (Qu’ils mangent de la brioche), was the response by an out-of-touch Marie Antoinette to the plight of the peasants who had no bread. Crops failed due to extreme weather from El Niño, amplified by the 1783 volcanic activity at Laki and Grímsvötn, Iceland. In Empires of Food, Evan Fraser and Andrew Rimas document over a dozen civilizations that rose and fell with famines caused by extreme weather events that were followed by war.

Lack of food can cause war and food often plays a central role in war. Barbara Clark Smith in Food Rioters and the American Revolution chronicled how scarce food, notably sugar, tea and bread in 1775, ignited the American Revolution. Historian Lizzie Collingham reported in The Taste of War: WW II and the Battle for Food that 20 million people, about half prisoners, died of starvation in World War II.

The 2011 Arab Spring parallels the revolutions across Europe in 1848. The “Spring of Nations” experienced a year food riots escalated into revolutions throughout Europe. The “hungry ’40s” saw a decade of bad weather that caused failed harvests. Hungry people in Europe became angry. Angry people organized to bring down governments.

Crop Failure and Food Riots

Conflict is also associated with extreme rainfall, particularly in societies dependent on agriculture. Higher rates of personal violence are found in low-income settings, where agriculture income suffers from extremely wet or dry conditions.


Shifts in temperature and rainfall influence economic productivity and food prices, which may spark discontent and food riots. Climate changes can force the displacement of entire populations, which destabilizes economic conditions and may lead to clashes over resources. Experts predict that several million people will migrate out of North Africa, where insufficient water is available to grow enough food crops.

Considerable evidence show that changes in economic conditions affect people’s decisions about whether or not to join a rebellion. Many of the young people that joined the revolutions in North Africa were unemployed and saw no realistic economic opportunity outside the army.

The Egyptian people were tolerant of their tyrant for decades – until they could not afford food for the family. Economic conditions change quickly when climate change spikes the price of food. When Egyptian families could not afford food, they took to the streets in food riots. The food riots escalated to revolution, which brought down President Hosni Mubarak’s government. Tunisian President Zine El Abidine Ben Ali fled to Saudi Arabia in January 2011 following the Tunisian revolution protests. Egypt and Tunisia ignited the Arab Spring that saw violence and revolution across North Africa.


Heat tends to amplify aggression in animals and in people. As heat increases, people’s patience decreases, as does impulse control. Hotter and drier weather causes an escalation in domestic and urban violence. Cooler and wetter weather cause people to stay indoors, and the threat of violence diminishes. Rising temperatures can lead to large-scale consequences over the entire planet.

Higher temperatures have been linked to innocuous behaviors such as horn honking while driving, as people’s tempers flare. Hostile behaviors increase with temperatures too, including domestic violence, assault, rape and murder.

Crop Failure and Food Riots

Normal human cognitive functions, brain activity, changes with rising temperatures. Severe heat feels unbearable to some people, and may alter their ability to reason and cause confusion. Inability to reason leads to an inability to interpret events correctly. The resulting misunderstandings can trigger conflict.

Path forward to prevent war

The scientific community agrees that human activity – burning coal, oil and natural gas – drives the rapid rise of CO2 levels in the atmosphere. Higher CO2 levels create a heat-trapping layer in the atmosphere that results in global warming. A July 2013 report from climatologists at Stanford Woods Institute for the Environment have warned the likely rate of temperature change over the next century will be at least 10 times quicker than any climate shift since the dinosaurs became extinct 65 million years ago.

The avoidance of temperature rise and the escalation of violence require new sustainable food solutions, despite climate change. The world needs solutions to free farmers from weather constraints and allow food production in nearly any climate. Increasing demand for food requires that at least some food production be climate independent.

Robert Henrikson and I propose developing peace microfarms to prevent violence and war. Microfarms can sustain food supplies, which will moderate the need for conflict. Microfarms distributed globally can moderate economic disruption, another source of violence. Microfarms do not provide a solution for the psychological or physiological triggers of conflict.Peace microfarms using covered, closed or hybrid designs can produce food 30 times more productively than modern agriculture, independent of climate. Therefore, climate change does not affect the food supply.

Microfarms are adaptable microcrop platforms that grow microcrops using sunshine, (or grow lights) and CO2. Growers can use any source for nutrients including and wastewater, brine water or ocean water. Of course, safeguards are necessary to kill pathogens and remove heavy metals, if they are present.

Abundance methods reinvent our food supply by growing food and other forms of energy with plentiful resources that will not run out. Microfarms do not compete with industrial foods because growers use renewable rather than fossil resources. Abundance and industrial food production are compatible and can produce simultaneously. Expanding populations need every available form of food production.

America needs a new national food security policy that recognizes and fast tracks microfarms. Microfarms will give farmers independence from weather, water and waste. Farmers will save money by practicing “recover and reuse” of their waste nutrients. Microfarms can deliver healthier foods with more nutralence – nutrient availability and density.

Peace microfarms using abundance methods enable growers to produce climate independent foods by cultivating the most productive crop on our planet — algae. Growing food organically, low on the food chain, yields sustainable advantages for consumers, growers and ecosystems. Abundance methods offer the opportunity to leave a superb legacy for our children — green fields, clean streams and affordable healthy food.