Approved by Canfei Nesharim Board of Directors, May 2009

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Summary: What is Happening

The Earth’s climate has warmed significantly over the last 50 years, and unless human activities change dramatically, will continue to warm throughout his century.

• Fossil fuels are burned as a result of things we do every day to eat, travel, and live in our homes.
• Greenhouse gases, such as carbon dioxide, nitrous oxide and methane, are released by the burning of fossil fuels (such as oil, coal, and natural gas).
• These “greenhouse gases” remain in the atmosphere for a long time and are causing our atmosphere to become warmer.
• In addition, destruction of forests and other changes in the way we use our land have increased carbon dioxide in the atmosphere.
• The rise in atmospheric greenhouse gases parallels the rapid rise in the Earth’s surface temperature during the same period of time.

It has been predicted by sophisticated computer models, demonstrated by carefully designed experiments, and confirmed by countless direct observations that increased concentrations of greenhouse gases in the atmosphere have profound effects on the Earth’s temperature, sea level, and the abundance and distribution of precipitation. 

Why Climate Change is Important

Global warming affects the health and welfare of humans and other living organisms on this planet. To date, the earth’s surface has warmed an average of 0.7oC and according to IPCC scientists, if no corrective action takes place, carbon dioxide concentrations will double by the latter half of this century, causing a rise of from 2.0 to 5.5oC (3.6 to 10oF) in the earth’s average surface temperature.[1]

While these temperature changes may seem small, it is important to understand that even these slight changes in the average surface temperature can have profound effects on the global systems that regulate our planet. One way to help put these temperature changes into perspective, one must understand what climate change means in terms of human health and welfare[2].

While climate change might allow those in northern latitudes to enjoy warmer winters, warmer winters generally reduce the snow pack that provides the drinking water resources for a region. Snow and ice from mountain glaciers and snow pack are primary sources of water for both surface water (lakes and rivers) and ground water (the water source for wells). For example, scientists have shown that glaciers are melting at an alarming rate and may disappear within 30-50 years[3],  with serious impacts on the water availability in those regions. Additionally, in many subtropical and tropical regions, increased heat will cause drying, expanding arid conditions.

Our water resources are used for agricultural, commercial, and domestic purposes. As population numbers increase and the demands for water rise, decreasing levels of available, usable water could create severe socio-political crises and economic disruptions. 

Beyond the need for water, a warmer planet can have significant impacts on agriculture. Warmer winters, earlier snowmelts and later frosts have been shown to cause greater insect infestations for agricultural crops. That is because many insects die during extended winter periods of subzero temperatures.[4] Additionally, while some species of crops grow better with increases in atmospheric carbon dioxide, the warmer, drier weather in some regions that are associated with increased carbon dioxide reduces overall productivity for many other key agricultural species.[5]

There is also a risk of warmer weather to human health. Aside from the very real risks posed by drought and heat stress (particularly to vulnerable populations such as babies and the elderly), there is also a potential for increased disease. Because changes in rainfall patterns and temperature regimens, may extend the range of mosquitoes that can spread malaria, yellow and dengue fever, populations that had not experienced waterborne diseases may now be susceptible.[6]

While many of us have heard predictions of sea level rise as a consequence of climate change, we do not realize that ocean islands may be completely submerged by this increase. This reality may create millions of environmental refugees as people flood into areas in search on potable water and arable land. A recent report from the United Nations projects that the sea level could rise as much as two meters by the end of the century. Sea level rise could have devastating impacts on the hundreds of millions of people currently living in densely populated coastal regions or mega-deltas of Asia and India. The United Nations estimates that a sea level rise of only one meter will cause some areas to be uninhabitable, such as the oceanic island nation, Maldives, where about 80 percent of the 1,192 coral islets are one meter or less above sea level [7].

The displacement of entire societies, most of whom have had no share in the causes of climate change, pose startling issues for human justice.

Scientific Evidence

Largely as a result of increased human activities, the atmospheric concentration of carbon dioxide has reached 385 parts per million, a 40% increase over levels in the pre-industrialized world [8] and the highest values known for the last 1 million years.[9] Atmospheric concentrations of carbon dioxide continue to increase at a rapid rate[10] with 75% of the increase in carbon dioxide emission occurring in the last half century.[11]

Because of the long lead-time between emissions and consequent atmospheric temperature change, the atmosphere is expected to warm another 0.6°C (1.1°F) due to emissions that have already taken place even if no additional greenhouse gases are added to the atmosphere.[12]

There is a strong scientific consensus that rising carbon dioxide and other greenhouse gases has caused temperatures to rise above pre-industrial times by about 0.7^oC (1.3^oF) and has brought the hottest weather on record for several years within the last decade.[13] Damage from climate change is predicted to be most severe for changes above 2°C (3.6°F) and a carbon dioxide concentration of 450 parts per million.[14] Combining these data, it is clear that the system has already experienced or is committed to some 65% of the warming we can safely afford.

Without any corrective action, carbon dioxide concentrations will double by the latter half of this century, resulting in a rise of from 2.0 to 5.5^oC (3.6 to 10^oF) in the earth’s average surface temperature.[15] Therefore, it is highly likely that significant changes in agriculture, health, and socioeconomic parameters will occur.

Some of the carbon dioxide emitted to the atmosphere dissolves into the ocean, thereby increasing its acidity. Ocean acidification and related worldwide changes in ocean chemistry have been shown to be detrimental to marine organisms such as reef-building corals and a host of economically important fish species.[16]

Current research cannot prove with 100% certainty that existing climate change does not have a natural component along with the human industrial influence. However, predictions climate scientists made 20 years ago as to the Earth’s response to increasing atmospheric carbon dioxide levels are entirely consistent with the actual changes that have occurred.[17] This powerful finding is matched by retrospective computer modeling that has demonstrated that the single most accurate predictor of current changes in land and ocean temperatures is the human-driven emissions of carbon dioxide.[18]

While there are uncertainties in the science of climate change, they are not about whether the Earth has already warmed or whether human emissions of greenhouse gases are responsible for a large part of this warming. Rather, they concern the magnitude of future changes if civilization does not take corrective action.

What Can Be Done to Help

Given that human activities are a critical cause of global climate change, Canfei Nesharim recognizes that people can also become motivated to act to reduce or even reverse the rate at which these changes are occurring. Specifically, as an organization we appeal to the full range of societal stakeholders to promote policies and practices that reduce carbon footprints at the individual, corporate, national, and international levels.