I'm a student environmental activist and in this project, I evaluated the nuclear weapon's impacts in an environmental perspective.
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<Environmental Contamination>
The atmospheric contamination is dominantly induced from the process of both nuclear weapon tests, and the actual explosion. As confirmed by Remus Prăvălie, the faculty of Geography at Bucharest University, approximately, 90% of all nuclear tests were conducted in the northern hemisphere, especially by the USA, China, and Russia, and 10% in the southern hemisphere, including the United Kingdom and France. The ecosystem contamination is mainly marked by the leaking and venting of chemical substances into the atmosphere, water bodies, and soil.
Currently, in the Nevada Test Site region, the correlation between underground tests and atmospheric contamination was substantiated by the considerable quantities of radionuclide I release into the atmosphere through venting in at least 32 cases of underground tests. Moreover, it was claimed to be the main cause for the Pu isotopes release, which contaminates groundwater through the hydrodynamic process with the risk of reaching the ground surface. One of the fatal contaminations that was conducted by the United States took place in Bikini Atoll, the island chain located halfway between Australia and Hawaii. Castle Bravo, a series of high-yield thermonuclear weapon design experiments, was conducted and invoked radioactive contamination. The absorbed radiation dose for the Earth’s crust in 1 year was documented as 6 Gy, though natural radioactive materials for the same period are conventionally accounted as 1m Gy. Thus, this demonstrates the downturn of the soil condition in numeric values and corroborates the idea of ecosystem contamination.
Assessed as Russia’s most prominent nuclear test site, the Semipalatinsk region is responsible for conducting 65% of Russia’s total experiment. Specialized studies have demonstrated that the Semipalatinsk region is deeply contaminated by radioactive isotopes, including Sr, Cs, and Pu. This has directly deteriorated the soil and led to the extent of portraying higher possibilities of vegetation failure. Another test site is Novaya Zemlya, where 20% of Russia’s nuclear testing is carried out. 70% of the test was considered an atmospheric experiment, which served as the main element to emit Cs and Pu radionuclides and cause global scale dispersion process in the atmosphere, which has already reached the stratosphere. Cs and Pu radionuclides were also found to be located in the marine waters as well.
The damage that occurred by the atomic bomb explosion also accounts up for the critical ecosystem’s aggravation. Historically, one of the nuclear bomb explosions which took place in Hiroshima was found to be the main cause of the black rain that degraded the bomb fallout region. After the bomb has exploded, its residue fused with the vapor inside the atmosphere and fell as a form of precipitation. Conforming to Doctor Masaharu Hoshi from the Research Institute for Radiation Biology and Medicine, the researcher has succeeded in calculating the soil contamination aroused by the black rain. The experiment progressed by obtaining the alpha ray spectra of uranium extracted from soil samples found in the bomb explosion area within 6 kilometers. The experiment suggested that the data for the “black rain” area show the increase of uranium isotope ratio according to the increase of the activated Cs. Because the atomic bomb substantially consists of uranium isotope and the process of the explosion has a strong relationship with the Cs fallout, it explains that the soil impurity was caused by the atomic bomb explosion. This soil impurity is the potential cause of water scarcity, as the radioactive elements within the soil can easily flow into the water bodies as the soil erodes.
Nonetheless, despite its responsibility for environmental deterioration, its direct impact on human beings isn’t considered significant, as it’s noted by Dr. Sakata R who majored in clinical psychology at Kyoto University. From 1950 to 2005, the excess relative risks level was pointed out as 0.08, which is relatively a low numeric value. The weak association for all-cause mortality in Hiroshima illustrates the indirect consequence of nuclear weapon usage on human health.
<Climate change>
Nuclear weapons’ development and usage are constrained to more than superficial environmental contamination; its impact on climate change is significant in means of its long-term effect on both environment and human beings. The progress of nuclear weapons effect on climate change can be supported by the scientific experiment that answers the initial hypothesis, or by analyzing the historical evidence and examples which were recorded during that period.
Scientifically, the experiment has proved that during the process of the explosion, the fireball generated by the nuclear weapon is responsible for the large numbers of dust particles in the submicron size- as it’s mentioned as “typical dimensions of less than one ten-thousandth of a centimeter”- as well as the nitrogen oxides in the atmosphere. Being difficult to be naturally removed from the air, dust particles reduce the total amount of sunlight reaching the earth's surface, and the nitrogen oxides cause stratospheric ozone depletion. This phenomenon answers the question of why nuclear weapon causes temperature decline as part of climate change. Furthermore, nuclear weapon detonation as directed towards cities ignites explosive fires that can create smoke particles. These particles are slowly elevated to high altitudes, where it impedes the sunlight penetration and modifies the heat balance. As a result, the ground temperature plunges. Another possible result states that the nitrogen oxides are changing the speed of the winds at high altitudes.
Historical evidence was acquired from the carbon dioxide analysis. During World War II where the nuclear weapon was widely used, the plants also ingested carbon dioxide, which contains the minuscule size of radiocarbon. After the plants die, or the animal that has consumed those plants dies, the radiocarbon in their remains decomposes, and non-radioactive carbon substance remains. This allows the scientist to track the carbon cycle. Using this method, the scientists were able to figure out the climate change that happened in 1963 due to the above-ground nuclear test. What scientists found out was the large quantities of radioactive carbon-14 produced from the nuclear test, which created the debris clouds in the stratosphere to the degree of doubling the atmospheric density and blocking the sunlight passing, as it’s illustrated in the picture below.
After the Manhattan Project, which was the project aimed for the research and development for the goal of producing the first nuclear weapons during World War II, the “nuclear winter” was observed due to climate change. Historically, the dust, sulfuric acid, soot, and other particles that were generated from the nuclear weapon were pointed out as the important cause. Climatologists claimed that the factor of 4 in the equilibrium dust concentration in the atmosphere would result in the mean surface temperature to decrease by much as 3.5 Kelvin. If this temperature is maintained over a period of decades, the overall temperature decrease would be adequate to provoke an ice age.
Fukushima radiation was also known for its effect on climate change, as the explosion ignited not only cities and forests but gas and oil fields, refineries, and other fuel sources that are highly concentrated. This resulted in smoke and photochemical-induced smog that darkened the atmosphere for several weeks, and “depleted the ozone layer by 65 percent at latitudes above 45 degrees” according to the National Research Council Study.
In 1983, two independent groups, one in the United States and another one in the Soviet Union (Current Russia), simultaneously started predicting the plausible dissemination of dust and chemical smog after the possible further nuclear weapon usage in a similar condition to the previous Japan occupation using climate models. The conclusion was similar: the smoke would soon be ubiquitous, disturbing the ecosystem functions and resulting in the northern hemisphere’s temperature dropping below freezing and remaining for more than six months.
The most updated NASA model predicts future climate change, under the assumption of one hundred of the same type of nuclear bomb which was used in Hiroshima (each packing the equivalent of 15,000 tons of TNT, which accounts up for only 0.03% of the world’s current nuclear arsenal) is dropped. NASA predicts that the resulting fires would start the fire and invoke 5 million metric tons of black carbon into the troposphere, or the lowest part of the Earth’s atmosphere. According to its model, global warming will become a long-term trend, as the global temperatures would drop by 1.25 degrees Celsius (2.25 degrees Fahrenheit) for more than two to three years. If it’s extreme, Asia, the Tropics, Europe, and even Alaska would experience a temperature decrease of 3 to 4 degrees Celsius (5.4 to 7.2 degrees Fahrenheit) (5). Because the average global temperatures would be lower than the period before the nuclear war up to 0.5 degrees Celsius (0.9 degrees Fahrenheit), the result is conceivably regarded as the nuclear winter. The same model also suggests that these changes are not only subjected to temperature modification but also the circulation patterns alteration in the tropical atmosphere, causing a 10 % precipitation reduction globally for one to four years.
<Famine>
Climate change is directly related to famine, as agriculture depends on the environmental status. The first specific reason for the famine is the chilling or freezing temperatures. The occurrence of short-duration events of low temperatures during the growing season is critical to the grain yields, as it’s both substantiated by the laboratory experiments and the historical record. The additional cloud generation would result in even greater temperature reductions for the brief time period; the estimation is roughly 1 degree Celsius to 5 degrees Celsius decrease for one or more years after the nuclear war. Second reason is the insufficient growing season length. This is mainly associated with the average reduction in temperatures over the spring-summer months that is predicted during the post-nuclear war period. The shortening of the length of the growing season will take place with the delay in the “occurrence of the last day of freezing temperatures in the spring and an early onset of freezing temperatures in the fall” (Harwell). For example, in the Northern Hemisphere continental regions of the mid-latitudes, a 1-degree Celsius reduction in average directly relates to a 10-day reduction of the growing season.
The graph above depicts the average temperatures and growing season lengths over severathel years in the multiple locations of the United States. The problem happens when the growing season is shorter than the growing season length required for the crop to fully mature. This problem further deteriorates as the reduced growing season temperature causes crop plants themselves to develop at a much slower rate, increasing the growing season length requirements to fulfill the maturity. The third reason is inadequate thermal times. Similarly, this is important for the crop to grow fully, as the crops under a certain threshold for thermal time can’t mature enough to reproduce. Disparate plants are subjected to different thermal time, the “measure of the number of hours during the growing season that air temperatures exceed a specific base level by various amounts and is calculated by multiplying the amount of time that the air temperature exceeds the base level times the increment of temperature above that level” (Harwell). A final reason is insufficient precipitation. The precipitation is directly related to the overall vegetation yields, as the 25 percent reduction in precipitation would lead to at least a 25 % reduction in crop yields, according to both computer simulation and historical analysis in global means.
With computer modeling, a 1-degree Celsius reduction in average temperature causes the decrease of the small potential crop growing areas. However, 2 degrees Celsius reduction in average temperature would result in the removal of the majority of potential crop growing areas. Finally, a3 degrees Celsius reduction would result in the elimination of complete possible cultivation areas (7). In the final stage, the damage to a human being is expected as the death of 2 billion people, only by the famine. This even suggests the risk of extinction of homo sapiens. Therefore, the nuclear weapon’s negative impact on the environment should be accentuated for maintaining the ecosystem and enhancing human life quality.
Writer: Chris Lee