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Climate Change | Biodiversity Loss | Health Concerns

Climate Change & Global Warming

Marah J. Hardt, PhD and Carl Safina, PhD, Blue Ocean Institute

Everything on Earth–water, air, soil, plants, animals, people, and all else in nature–is woven into the fabric of Creation. Tug one part of the cloth, another part feels the pull. Earth receives heat from the sun and reflects much of it back into space. Certain gases in our atmosphere trap some of the heat, like the glass of a greenhouse, giving the planet life-sustaining warmth. This is called the “Greenhouse Effect” and the gases are called “greenhouse gases.” Without this effect, Earth would be too cold for life.

But there can be too much of a good thing. Greenhouse gases now emitted by human activities—mostly by burning fossil fuels such as coal, oil and natural gas—are building up in the atmosphere and trapping more heat. Carbon dioxide, one of the strongest greenhouse gases, increased 35% between 1850 and 2007 as the world industrialized, going from a concentration of approximately 280 parts per million to over 380 parts per million, and rising (meaning that for every million molecules of all gases in the atmosphere, 380 are carbon dioxide molecules).

Scientists can measure layers of ice just like tree rings and extract air that was trapped in bubbles when the ice was formed thousands of years ago. By measuring the carbon dioxide in the trapped air, we can know how much used to exist in the atmosphere. Today, there is more carbon dioxide in the atmosphere than anytime in past 400,000 years. The result is a warming planet. Eleven of the past twelve years (1995-2007) rank among the 12 warmest since reliable measurements began in 1850.

This warming cannot be explained by changes in the sun’s strength, or other natural phenomena. But it can be explained by human activities, primarily burning fossil fuels and land use changes. In fact, that is the only source for the warming that appears possible, and that makes sense given scientific understanding of the atmosphere and how it works.

Why does climate change matter? Many of the effects of climate change are a little surprising. For example, climate change threatens our supply of drinking water. Warmer temperatures change rainfall patterns and also melts glaciers. These glaciers are Creation’s natural storage tanks, supplying freshwater to over a billion people through slow spring melting. Smaller glaciers melting too soon and too fast means less water for over 1/6 of the world’s population, many of them in poor, rural areas, such as in India or China. This will increase poverty, desperation, food stress, and strife.

Warming temperatures also cause changes in the growing season, affecting agriculture. Climate change also disrupts the timing of natural events, such as bird migrations or blooms of algae in the sea, which results in the loss of breeding or feeding opportunities for species. Animals and plants that need colder climates are at risk because they can only move so far north or south towards the poles, or uphill on mountains. Eventually, they run out of habitat. In the sea, unusually warm temperatures are killing tropical coral reefs in large areas worldwide.

Overall as the average temperature of the globe increases, the weather around the world becomes less stable with more extreme events, including droughts, floods, and bigger storms. Warmer air holds more water vapor, which then leads to bigger rain storms. But warmer temperatures also mean increased evaporation of water from the ground. The combination results in wet places getting wetter, and dry places becoming dryer. Sea level is also rising, as more glaciers melt and warmer ocean water expands. Communities from tropical islands in the South Pacific to islands off Alaska in the Arctic are threatened by loss of habitat and changes in their ancient customs that depend upon natural cycles of hunting, fishing, and harvesting that are now disrupted. Millions of people in low-lying cities (half of humanity lives within 50 miles of a coast) and in crowded regions like Bangladesh will have to move as saltwater begins to taint their fields or flood their homes. Where will they go?

Oceans are another large sponge for carbon dioxide gas, absorbing almost half of all the carbon dioxide emissions that humans have released into the atmosphere since industrialization. The extra carbon dioxide is changing the chemistry of the water, making it more acidic, which affects the ability of animals to live there. When carbon dioxide dissolves in seawater, it binds to carbonate ions, taking them out of circulation. Fewer carbonate ions makes it harder for animals such as corals and many mollusks to build strong, thick shells. These animals must spend more energy building skeletons and shells, diverting energy for growth and reproduction. If we continue with current trends in fossil fuel consumption, scientists predict ocean waters will become too acidic for corals as early as 2050. Meanwhile all organisms in the sea have to expend more energy to balance their internal chemistry in changing chemical conditions. These changes ripple through the food web, affecting fisheries, and weakening coastal protection by coral reefs.

The effects of putting carbon dioxide into the air are partly determined by other things we do, too. Plants absorb carbon dioxide from the air and with a little sunlight and some water, their green chlorophylls create sugar and release oxygen as a “waste product” of the process (which is called photosynthesis, meaning ‘making with light’). Cutting down trees reduces the ability of the earth to absorb carbon dioxide, which only exacerbates the warming.

Climate change permeates all aspects of our lives, from the food we eat, to the water we drink, to the places we can live. People depend upon other strands in the fabric of Creation for a stable, healthy existence. Climate change is slowly loosening this fabric. We must take immediate action to prevent unrecoverable harm. Fortunately, the main things we need to do, like using more energy-efficient products and developing new energy sources, will also be good for our national security and our own wallets. That’s another way in which things are all connected.

Marah Hardt and Carl Safina work with Blue Ocean Institute. You can see their profiles and other aspects of BOI’s work at

Top Resource on Global Warming:
Intergovernmental Panel on Climate Change

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Pastoral Perspective

by Steven Bouma-Prediger

The evidence for global climate change has gotten more certain with each passing year. The debate about whether it is real is over. The important questions are: what will be the consequences and what can we as humans do to prevent the worst? One of the profound effects of global warming is loss of biodiversity. Our original world wide web—biodiversity not the internet—is becoming frayed and torn. Some reputable scientists claim that we are at the beginning of a massive extinction. But we humans cannot live without the plethora of creatures around us. Our lives depend on theirs. Finally, the effects of both of these degradations will affect the poor and impoverished the most. We in the wealthy parts of the world will adjust, but a great many people will not be able to.

For Christians, this is simply unacceptable. Integral to our faith is the call to care for the earth and its panoply of creatures. Even if we did not have serious ecological problems, the Bible teaches us to care for creation. For example, Genesis 2:15 calls us to serve and protect the earth. Like the slogan on the side of every Chicago police car (“To serve and protect”), we humans made from the humus are given the responsibility and the joy of being creation’s cops—watching over and protecting as well as cultivating and using the gifts of the earth. And the Bible teaches us that we must give special attention to those most vulnerable—the modern equivalents of the widows, orphans, and aliens of Old Testament times. The question is: will we?

Dr. Steven Bouma-Prediger
Professor of Religion
Hope College, Holland, Michigan
Author of “For the Beauty of the Earth

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Biodiversity Loss

Biodiversity is the variation of life forms within a given ecosystem, biome, or for the entire Earth. The different species of plants, animals, and microorganisms, the diversity of genes in these species, and the different ecosystems such as deserts, rainforests, and coral reefs, all are an integral part of Earth’s biodiversity. Biodiversity is often used as a measure of the biological health of a given ecosystem. As many as 30 million different species are thought to live on Earth, but only about 1.5 million have been documented by scientists.

Species Loss
Despite the incredible diversity of life, some studies show that between 10 and 30 percent of all bird, mammal, and amphibian species on the planet are currently threatened with extinction, and many other forms of life face similar conditions. Though extinction is not a new phenomenon, the extinction rate is now about 1,000 times the historical background rate, and may increase to 10,000 times by 2100. This translates into a permanent loss of about 25,000 species of life per year, or about 1 species every 20 minutes. According to several comprehensive studies, the increase in extinction rate is attributed entirely to human activities.
Habitat fragmentation and destruction, the spread of introduced species, and overfishing/overhunting are the leading causes of species extinction. Climate change, which can force changes in a species’ relation to its habitat, is becoming a major concern for extinction trends in the near future. It is often a combination of these stressors that ultimately causes a species to go extinct.

Benefits to Humans
Biodiversity has a variety of direct benefits to humans that warrant its protection. At a basic level, humans rely on the rest of life on Earth for food. Although 80 percent of our food supply comes from just 20 different plants, humans use about 40,000 species of plants and animals each day for food and drink. The dependence on only a few crops can lead to agricultural disaster, such as the Irish Potato Famine in the late 1800s. Earth’s store of species and genetic diversity has allowed us to find new varieties of crops that increase yields and resist pests. Also, many of the world’s medicines are derived from biological sources, and many of these cannot be artificially synthesized in a lab. Only a tiny fraction of organisms have been evaluated as potential sources of new drugs, and the maintenance of biodiversity ensures these sources remain available for future discovery. For example, the pacific yew, formerly considered an undesired tree in many settings, contains taxol, a chemical which was recently found to effectively fight against lung and ovarian cancer. Across the planet, many other products such as construction materials, fuel, fibers, resins, dyes, and other industrial and cultural materials are derived directly from the natural world. The long-term status of these materials depends solely on the survival of healthy, diverse ecosystems.

Ecosystem Services
Aside from extractive potential, healthy ecosystems perform many other functions that directly or indirectly benefit humans and other organisms. All ecosystems have a role in regulating the chemical and biological cycles that are the lifeblood of our planet. For example, many forests help build fertile soils, moderate local climate, filter water, and recycle carbon and other nutrients. Other ecosystems such as wetlands provide flood protection, erosion control, water treatment, help replenish groundwater, or provide other valuable services. Mangrove forests, for example, effectively protect against hurricanes and tsunamis along tropical and subtropical coastlines. Insect pollination of crops, a service valued at tens of billions of dollars annually, is provided for free by the inhabitants of healthy ecosystems. Preserving the biodiversity of these ecosystems ensures that they will continue to provide valuable services long into the future. In some cases, the loss of one or a few keystone species can lead to the unraveling of an entire ecosystem and thus the loss of ecosystem services.

Cultural and Aesthetic Value
Many people derive value from biodiversity through the simple enjoyment of nature, an ecosystem service that is hard to quantify. Birdwatching, hiking, and camping are popular ways that people appreciate nature, and people often feel refreshed or restored after such activities. The aesthetic nature of biodiversity has long been a source of inspiration for writers, musicians, and other artists. Other people feel a moral or religious obligation to enjoy and protect biodiversity, and many cultural groups view themselves as an integral part of the natural world and have a deep respect for other living organisms. Many of these people would argue that biodiversity is worth protecting even aside from the quantifiable benefit to humans.

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Health Concerns

“…Truly I say to you, to the extent that you did it to one of these brothers of Mine you did it to Me.” Matthew 25:40

The public health consequences associated with anthropogenic (caused by human activity) changes in the local and global environment are numerous, diverse and difficult to predict. However, one commonality shared among these adverse health outcomes is that children, elderly, chronic disease sufferers and, most significantly, the global poor are disproportionately affected at significantly higher rates than healthy, economically advantaged populations. While the cumulative anthropogenic effects on the global environment are innumerable, climate change, both general global warming as well as increased frequency of extreme weather events, and air pollution represent the most significant and direct contributors to negative consequences for public health.

Climate Change/Global warming
In their 2007 report, The Intergovernmental Panel on Climate Change (IPCC), an international collaboration of more than 2,000 environmental scientists, concluded that global warming is “unequivocal” and it can be attributed, with greater than 90% certainty, to the activities of mankind. Because the interactions between humans and the environment are endless, changes in the global climate, however subtle they may be, undoubtedly result in endless consequences for human health. The complete impact of global warming on human health has yet to be elucidated, however, many direct effects are already being observed.

The most obvious effects related to global climate change are the redistribution of old infectious diseases (ie: Malaria, Dengue and Yellow Fever) and the emergence of new diseases (ie: West Nile Virus). As an illustrative case study, malaria is useful in demonstrating this relationship between climate change and increased spread of infectious disease. Malaria is a chronic disease caused by parasitic infection of the red blood cells by Plasmodium protozoa causing flu-like symptoms, kidney failure, anemia, seizures, bleeding and, in some cases, death. The protozoa that cause malaria are transmitted exclusively by the Anopheles mosquito and the disease is therefore limited geographically by the range of the insect. Previously, cities such as Nairobi, Kenya and indigenously populated rural areas such as the New Guinean highlands were essentially protected from malaria by their relatively cool climates due to high elevations. However, as the isotherm (the altitude at which water remains frozen year round) ascends, so does the altitude which can be inhabited by the Anopheles and vectors (carriers) of other diseases. 300-500 million new cases of malaria occur worldwide each year and it remains the most common cause of mortality among children under 5 in Sub-Saharan Africa resulting in 1-3 million deaths annually. As the range of the mosquito vector continues to increase, these numbers are projected to rise despite the fact that the disease is easily preventable and curable, with a total cost per cure being less than $1.50 (US). Malaria is a leading cause of work absence and total years of life lost in Africa. The increasing occurrence of the disease is crippling to the work force, further promoting a nearly inescapable cyclical pattern of disease and poverty. A comparable pattern of redistribution is occurring with Lyme disease, caused by the bacterium Borrelia burgdorferi, in North America as the range habitable by its vector, the Ixodes tick, increases in a similar fashion.

Air Pollution
Although often used to refer primarily to automobile exhaust and industrial waste, environmental scientists consider air pollution to include any contaminants, biological, industrial or otherwise, that disrupt the inherent balance of Earth’s atmosphere. The contaminants that impact human health most significantly are fossil fuel combustion products and aeroallergens. Air pollution resulting from fossil fuel use can be divided into primary products of combustion and secondary chemicals created when primary products react with other atmospheric molecules creating a mixture called photochemical smog, which exists in the highest concentrations in urban centers. Increasing concentrations of photochemical smog, which contains ozone and other strong oxidizing compounds that can damage respiratory airway tissues, is believed to be associated with the 160% increase in the occurrence rates of asthma in preschool aged children between 1980-1994. Within this group, the rate of increase in asthma was higher among African-American children and those from low-income families according to the CDC. In addition, photochemical smog has been proven to cause asthma exacerbations which can be fatal in situations without access to bronchodilating medications.

The term aeroallergen refers to any aerosolized particulate organic matter that causes allergic reactions. Among the most common aeroallergens are ragweed pollen and mold spores. Scientists have shown that ragweed (Ambrosia artemisiifolia) produces more pollen in warmer environments as well as those with higher concentrations of CO2 and thrives in areas of cleared or disturbed ground; all of which are fostered by human activity. While allergic rhinitis (hay fever) may be only a nuisance to many sufferers, such allergic reactions may precipitate potentially fatal respiratory compromise and heart failure requiring hospitalization in those suffering from COPD, a chronic lung disease of the elderly.

Extreme Weather Events
Extreme weather events (EWE), commonly referred to as natural disasters, include droughts, fires, floods, heat waves, tsunamis and wind storms. The patterns of global climate change observed during the past century have been associated with a significant increase in the frequency and severity of each type of EWE. The repercussions of these events are more devastating for residents of developing countries (ie: sub-Saharan Africa) and the poorer populations of developed countries (ie: U.S. and Western Europe) because these individuals typically lack the basic resources necessary to cope with the physical stress of the event and its aftermath.

The impacts of EWE’s on the populations affected can be classified as either direct or indirect health consequences. Heat waves have increased in duration and intensity secondary to global warming. This phenomenon is most pronounced in cities where summer nighttime minimum temperatures have increased dramatically over past decades. The “Urban Heat Island Effect,” to which this is largely attributable, is a process of nighttime warming during summer months related to land modification, specifically the replacement of vegetation with concrete and asphalt. The direct effects of heat waves are hyperthermia, or “heat stroke,” which can result in permanent brain damage and cardiovascular collapse, and dehydration, which is rapidly fatal in severe cases. These outcomes are experienced at disproportionately high rates by those living in urban centers without nearby parks, those without indoor climate control, those with poor access to health care/uninsured individuals and the elderly. 81% of the deaths in Paris directly related to the 2003 European heat wave, which killed an estimated 30,000, were individuals over 75 years old.

As oceanic and atmospheric temperatures rise, both evaporation from bodies of water and the atmosphere’s capacity to hold water increase leading to greater torrential rains in many regions. Flooding is the most common natural disaster comprising roughly 40% of all EWE’s worldwide. Direct health effects of flooding include traumatic drowning and wound infection. However, the indirect consequences are more abundant. Flood waters often contaminate reservoirs and wells leading to outbreaks of water-borne infectious diseases such as typhoid (salmonellosis), dysentery (amebic or shigellosis), Hepatitis A and cholera, all of which can lead to fatal dehydration. The flooding of the Mississippi River valley in 1993 led to an outbreak of Cryptosporidium parvum, a water borne protozoan, affecting over 400,000 individuals exposed to Milwaukee’s contaminated public water supply. Some areas, such as Western Europe, that experience summer flooding will experience winter droughts. These droughts are associated with exceedingly high rates of forest fires. Smoke from forest fires can contribute to photochemical smog leading to increased rates of asthma and COPD exacerbations in nearby populations. The mental health of populations can also be adversely affected by natural disasters. Rates of major depressive disorder, generalized anxiety disorder and post-traumatic stress disorder have been found to increase in association with experiences surrounding extreme weather events such as loss of loved ones, personal injury and property damage.

The Future
Earth’s biosphere is a complex network of interactions between living and non-living components of the global environment. From driving inefficient cars to cooling our homes with electricity generated from fossil fuels, substantial causal links exist between human activities and negative public health outcomes, especially concerning our disadvantaged neighbors in the global community. Furthermore, future impacts of unabated climate change are likely to transcend socioeconomic divisions and involve insufficient agricultural capacity and potable water supply to support an exponentially growing human population.

It is clear we have negatively affected our planet, however, we should be encouraged that if we choose to affect the Earth in positive ways, many of these situations we have created, which lead to death and disease, can be counteracted by improving our behaviors across the residential, commercial and industrial sectors.

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