Health and Environment
Ozone layer is one of the earth’s atmospheres known as stratosphere. The layer surrounds the earth at a height of twenty-five kilometers from the earth’s surface. The most fundamental purpose of this layer is to prevent harmful ultra-violet rays of the sun from reaching the earth’s surface. Ultra-violet rays have diverse effects on every living organism, including crops, marine life, birds, animals and humans. Therefore, depletion of the ozone layer can cause negative effects on all living organisms (New Zealand, 1995). New Zealand is in Southern sea and southern Pacific and has an extraordinary clean atmosphere. Most parts of the country enjoy such atmosphere. The existence of a clean atmosphere is mainly because of the country’s low population mean density. Also, due to little or short lived particulates and industrial gases that affect the area. he country’s clarity and latitude of atmosphere imply that high levels of ultra-violet radiation from the sun reach the ground unhindered. As a result, there are higher levels of ultra-violet radiation in New Zealand’s ground level than in any other developed country. Ozone depletion exacerbates this effect increasing the intensity of ultra-violet radiation that causes sunburns. The high health and environmental impacts of increased ultra-violet radiation can be severe. That is the reason New Zealand experiences a high level of ultra-violet radiation (New Zealand, 1998).
Ozone depletion occurs because of man -made chemicals. These chemicals contain chlorofluorocarbons and other halogen depleting substance. The presence of these chemicals in the atmosphere is entirely due to human activities. They occur due the usage of cooling units and air conditioning systems. They can also occur due to by-product chemical processes. These chemicals get dissociated by the rays when they reach the stratosphere. As a result, they release chlorine atoms. These atoms of chlorine act as a catalyst that breaks down the stratosphere. Each atom of chlorine breaks down thousands molecules of ozone before its termination from the stratosphere. Chlorofluorocarbons have an exceptionally long lifespan and their recovery measure go for decades. Each chlorofluorocarbon takes a mean of five to seven years to move from the earth’s level of the upper atmosphere, where it stays for a century destroying up to a hundred thousand of ozone molecules (New Zealand & Connell Wagner Limited, 1998).
There are several factors that cause ozone depletion, the main being the use of chlorofluorocarbons. But in New Zealand, the major cause of ozone depletion is its position and latitude on planet earth. As a result, the negative effects of ozone depletion in New Zealand are as follows;
Ultra-violet light radiation affects developmental and physiological processes in plants. It changes the manner in which nutrients are distributed within the plant, secondary metabolism and timing of phase development. This type of changes causes significant implications such as, competitive balance, plant diseases, and herbivore and biochemical cycles. The increase of ultra-violet radiation from the sun has diverse effect in the crops. Economically valuable plant species such as rice depend on bacteria, which resides on their roots for the retention of nitrogen. On terrestrial plants, the effect of the ozone layer includes reduction in yield, decrease in photosynthesis activity, alteration in the competition of species susceptibility to diseases and change in plant pigmentation and structure. The sensitivity of cyan bacteria to ultra-violet radiation is extremely high and hence its increase would affect the performance of the crops (New Zealand & Connell Wagner Limited, 1998).
The reduction in crop yield occurs due to direct increase and damage diversion of crops or plant resources towards acclamation and protection. As the depletion of ozone continues, long-term effects are evident in plants such as, reduced plant growth. It is the global environmental changes that cause changes in ultra-violet radiation. As a result, all the terrestrial ecosystems are in danger. Specific changes in vegetative cover due to deforestation, aridity and cloud cover predict the occurrence of large impacts on levels of ultra-violet radiation received by terrestrial organisms (New Zealand, 1998).
The occurrence of moderate decrease in ultra-violet sensitivity in plants decreases precipitation but, temperature increase due to change in climate. Therefore, there is a restriction in plant growth, and plants compromise, to re-distribute resources to ensure protection from ultra-violet radiation and other factors that affect climate. On the other hand, ultra-violet radiation is the main agent in the breaking down of dead plant material, hence loss of carbon to the atmosphere. The breaking down of any dead material by sunlight is particularly crucial to all ecosystem processes, especially for those materials that decay exceedingly slowly through microbial action. Once, there is depletion of stratosphere ozone, levels of ultra-violet radiation increases. As a result, the rate of breaking down any dead material by sunlight through microbial action increases. This has a large effect on pests’ interactions with plants. Therefore, it creates food insecurity and quality. New Zealand depends considerably on agriculture for consumption and export. Therefore, the effect of depletion of the ozone layer has diverse effect on agriculture. From, the field to storage, farm are threatened with the spoilage of their produce (UNEP, 1992).
Additionally, phytoplankton shapes the aquatic food webs foundation. Their productivity restricts itself to the zone known as euphotic. The euphotic zone is the water column upper layer which has sufficient sunlight to promote net productivity. Therefore, the survival of the organisms in this zone is subjective to the action of waves and winds. In addition, many of these organisms are proficient of active movements that promote their productivity hence, their survival. When these organisms subject themselves to high levels of ultra violet light, their motility and orientation mechanisms get affected. As a result, the survival rates of these organisms reduce as decreases mobility, and changes in enzymatic reactions and photosynthesis reaction are affected. This leads to the reduction of productivity in primary level, which affects higher trophic level indirectly (New Zealand, 1995).
On the other hand, ultra-violet radiation cause damage in fish, crab, shrimp, amphibians and other animals during the early stages of development. The greatest severe effects are the decrease in reproductive capacity larval impaired development. Also, the limiting factor is that, any small increase of ultra-violet light can result to significant reduction in the animals population size that feed on these smaller creatures. This implies that the population that is in the outside of the local ecosystem is potentially at a risk.
Other organisms that are affected by the ultra-violet light in the aquatic ecosystem are the prokaryotic microorganisms. They are responsible for the fixation of nitrogen but highly susceptible to high ultra-violet radiation. As a result, they change nitrogen biochemical cycle leading to effects that are detrimental on plant growth. The other effect of increase of ultra-violet radiation is the decrease in the production dimethylsulfide by planktons, a significant cloud condensation nuclei and sulfur source to the atmosphere, and reduced carbon dioxide uptake by the ocean.
Negative effects of ozone depletion are worsened by environmental pollution. Ultra-violet radiation has a tremendous impact on aquatic ecosystems in places polluted by heavy metals such as copper, selenium or cadmium and crude oil. As the climate changes due to the ozone layer depletion, it alters the exposure of aquatic organisms to ultra-violet radiation. This occurs when the changes of the climate influences theocratic organisms depth distribution and transparency of water. The climatic changes increase the temperatures and as a result, the upper mixed layer depth decreases, hence, exposing aquatic organisms to elevated irradiances. This effect is truly minimal in New Zealand due to rare industrial activities that engage in the production of these metals (New Zealand, 1995)
In most coastal areas and inland waters, dissolved organic matter influences ultra-violet radiation transparency. Since human pathogens are sensitive to ultra-violet radiation, changes in dissolved organic matter alter their inactivation and exposure with increasing temperatures. This negatively affects all seaweeds that have economical and ecological importance.
Biochemical cycle is the transformation and transport of substances through water, land, living organisms and the atmosphere. Ultra-violet radiation interacts with the change in climate to drive the carbon cycle. These interactions accelerate the rate at which atmospheric carbon dioxide increases. Increase in solar ultra-violet radiation affects aquatic and terrestrial biochemical cycles. This alters both the sinks and sources of chemically prime and green house trace gases. Such gases include carbon dioxide, carbon monoxide, carbonyl sulphide and other gases including ozone. These crucial gases add to biosphere-atmosphere effect that reinforce or attenuate the buildup of these gases in the atmosphere (UNEP, 1992).
Changes in climate in New Zealand ecosystems increase the run-off. This accelerates the ultra-violet radiation. Hence, induce the breakdown of organic carbon in the soil into atmospheric carbon dioxide and hence reduce water clarity. On the other hand, the impact of pollution of air on the environment and human health occurs due to changes in the climate, ozone layer depletion and emissions of pollutants. Ultra-violet radiation forms one of the factors controlling the formation of photochemical smog that includes aerosols and trosopheric ozone.
Solar ultra –violet radiation adversely affect synthetic polymers, commercial interest materials and naturally occurring biopolymers. Even though today’s materials have additive which protect them from the ultra-violet radiation, any increase in the radiation levels accelerates their breakdown, reducing the length of time they are useful on the outdoors .Majority of man -made natural materials are used widely in outdoor agriculture, construction and other applications. The amplified rate of degradation at higher temperatures only depends on the rate of degradation at the higher temperatures and the precise material, the expose of geographic location and the ultra- violet environment radiation. Therefore, wood plastics and nanocomposites are widely applicable on most outdoor applications. This is due to their relatively high ultra-violet radiation stability in comparison to conventional materials (New Zealand, 1998)
High levels of ultra-violet radiation have extremely detrimental effects on humans such as skin cancer, tumors, and other types of skin damage such as sunburn and skin aging. Melanoma is the most dangerous form of cancer usually occurs among the young adults and adolescents. Even though this type of cancer causes three percent of all skin cancer occurrences, it causes skin cancer deaths of more than seventy-five percent. Ultra-violet sunburns and exposure especially during childhood forms the main factor that causes this disease.
Skin cancers such as, non-melanoma is less fatal than melanomas. If untreated, they can spread and cause disfigurement and serious health problems. The two main types of non-melanoma cancers are squamous cell carcinomas and basal. If treated at an early stage, the two cancers are less fatal. Basal cell carcinomas form the most common form of skin cancer tumors. They generally appear as small, nodules or fleshy bumps on the neck and head and other skin areas. This disease grows gradually and hardly spreads to other body parts. It can, however, infiltrate and cause damage that is so considerable to the bone. On the other hand, squamous cell carcinomas appear as nodules or as scaly, red patches. This type of cancer can grow into large masses and spread to other body parts.
Other ultra-violet radiations associated with skin disorders include premature skin aging and actinic keratoses. Actinic keratoses are growths in the skin that occur on those body parts exposed to the sun. The hands, forearms, face and neck are susceptible to this type of disorder. Premature aging is because of chronic exposure. This causes the skin to be thick leathery and wrinkled. Since it happens gradually, it is unavoidable (New Zealand, 1995)
High exposure of the human body to high levels of ultra-violet light has an extremely harmful suppressing effect on the immune system. For instance, sunburns change the function and distribution of white blood cells fighting disease in humans. This occurs for a period of up to twenty-four hours following exposure to the sun. The body’s immune system can be more damaging if overexposed to ultra-violet radiation reoccurs.
The human body gets defense from the immune system against viruses, parasites, toxins, microbes and bacteria that may cause diseases and infection. The immune effectiveness of a body or organism can be realized by how quickly an organism decays after dead and how fast the the immune stops working.
Cataracts are a type of eye damage that is a loss of lens transparency of the clouds vision. If this condition is untreated, it can result to blindness. Ultra-violet radiation increases the chances of certain cataracts. Even though they are curable through modern surgery, they diminish the eyesight of many citizens. Another type of damage is pterygium which is the blocking of vision by growth of tissue. There is also skin cancer that occurs around the eyes and degeneration of the macula.
There exist strong relations between depletion of the ozone layer and changes in climate. Inducement of these interactions occurs because of increasing greenhouse gases. Depletion of the ozone layer affects the climate and as a result, climate changes affect ozone. The increase in the concentration of green house gases affects the amount of stratospheric ozone. This leads to temperature decrease in the stratosphere and the acceleration of circulation patterns. As a result, there is a decrease in the total amount of ozone in the trophics as well as total ozone increase at high and mid latitudes. Also, circulation changes induced by ozone changes also affect patterns of rainfall and wind surface.
Chlorofluorocarbons are halogens which are synthetic substances containing bromine or chlorine developed in the 1930’s as safe, non-toxic refrigerants and non-flammable. There was extensive use until a discovery occurred in 1980s. The discovery indicated that chlorofluorocarbons were the source that was causing harm to the ozone layer. The most outstanding feature about New Zealand is that, it is had never manufactured chlorofluorocarbons. In addition, its usage pattern differs from that of other several overseas countries. The usage of chlorofluorocarbons as solvents in electronic industries was minor. Therefore, the application in aerosols was terminated in the late 1980s. In the 1990s, chlorofluorocarbons were less or more evenly splinted between refrigeration and foams sector. As a result, these chlorofluorocarbons were a minor contributor to depletion of ozone stratosphere in New Zealand (UNEP, 1992).
Like many other countries, the real amount of chlorofluorocarbons still in application in New Zealand is uncertain. On the foundation of the quantities imported until the 1996, ten to twenty thousand tonnes of chlorofluorocarbons might remain in air conditioning plant, industrial refrigeration systems, old domestic refrigerators and car air conditioning. Relationship between refrigeration industries and government agencies is open and constructive. As a result, controlled substance consumption and their willful release to the atmosphere are illegal. Another policy issues is that, New Zealand has laid down a strong reliance on deliberate measures. Every refrigeration and air-conditioning industries together with local authorities implement recovery programmes.
Diverse effects of the ozone layer depletion in New Zealand led to the initiation of a commitment on all those substances that their usage leads to depletion of the ozone layer. These commitments are in the Ozone layer Protection Act 1996. This act contains rules relating to specific substances. The majority of the controls stress on the importation of bulk substances. The act lays down broad controls for ozone-depleting substances. These provisions prohibit the manufacture, sale, export or import of such substances apart from those indicated under the regulations act. Also, the New Zealand Environment Minister requires people that deal with ozone depleting substances, to create codes of practice or know their obligation and have enough knowledge to fulfill them (UNEP, 1992).
On the other hand, the provision indicates that, it is an offence to break the provision or to allow the release of controlled substances knowingly during servicing, operating, installation and dismantling equipments. The regulation also prohibit the importation of freezers, dehumidifiers, supermarket display cases, refrigerators, water coolers and heat pumps that contain chlorofluorocarbons except when there are part of equipment. The New Zealand provisions contain essential features. One of the features is that, it indicates a full list of controlled substances. Another feature is the prohibition on the export or import in bulk processing of most controlled substances. Also, it provides for the importation of methyl bromide under the permit for quarantine, soil fumigation and shipment purposes. In addition, the provision indicates the phasing out schedule for chlorofluorocarbons and details of the importation permit system in use when the phase period is on (UNEP, 1992).
New Zealand’s location and latitude gives it no option of avoiding increased levels of ultra violet radiation. Other control measures may be observed, but still the country will always encounter the high level of ultra violet radiation. New Zealand has been successful to incorporate considerable flexibility in the laws. This has enabled New Zealand to respond easily to changing obligations. The primary obstacle in the phasing out of ozone depleting substances is the availability of economically and technically feasible alternatives for their usage. Therefore, the speed and effectiveness of international efforts to decrease ozone depletion in global environmental forum is unprecedented.