By : W.A. Harshani Abayawardhana (B.Sc(Hons)Env.Sci.) – Environmental Officer
Centre for Environmental Justice
Climate change, a broad range of worldwide phenomena of climate alteration, has emerged as one of the most pressing challenges today. These phenomena include changes such as sea-level rise, warming oceans, heat waves, glacier mass loss, habitat disruption, altering lifecycles, alterations in flower/plant blooming, and extreme weather events, in addition to the elevated temperature trends outlined by global warming. Climate change is defined by alterations in the planet’s normal climate in terms of temperature, precipitation, and wind. Human actions are mostly responsible for climate change.
Sri Lanka, as a tropical country, is particularly sensitive to the effects of climate change. Sri Lanka’s coastal region is vulnerable to increasing sea levels because it is a small island in the ocean. The majority of species that live in a tropical country are extremely susceptible to weather changes. The impact of climate change is now evident more than ever.
One of the most significant effects of climate change is habitat destruction. Storms cause destruction on nesting trees, spread invasive species that harm animals, and cause problems in aquatic ecosystems. Direct destruction and competitive exclusion are two primary threats to Sri Lanka’s native biodiversity posed by invasive alien species. Plants and animals are also stressed by high temperatures and droughts. Many wild species that reside in the dry zone, which were not observed in the previous wet zone, are now abundant in the wet zone: peacocks, for example.
High temperatures cause life cycles to alter. As an example, for some animals having life cycle with aquatic larvae stage, have both direct and indirect impacts. Higher water temperature can lead the higher mortality rate in developing larvae. Also aquatic larvae that develop in warmer water tend to develop smaller wings compared to body size. As the relative wings size decreasing, they will experience in less dispersal ability. Warmer water also causes the larvae to develop more quickly and emerge as adults sooner, thus affecting seasonality1. Furthermore, many experts agree that global warming can alter the timing of several natural cyclical events in animals’ lives. As a result of unfavourable condition, some species face reducing their chances of successful reproduction and also cause direct mortality
Droughts of historic proportions have occurred in recent years as a result of rising temperatures and less rainfall. Long dry spells cause crops to wilt and forest fires to erupt. This can lead to severe changes in ecosystem composition, including the extinction of species, habitat loss and the destruction of animal breeding sites. Drought serves as a major reason for water scarcity and that is led to the loss of animal lives, weakening the animal immune system, loss of animal nourishing, and increasing parasites and infectious diseases of animals
More frequent and severe occurrence of extreme rainfall anomalies such as floods strongly affect the aquatic and terrestrial species, that is to say, disturbance of the life cycle, disruption of the habitats, loss of nesting/breeding places. Also, the animals can get displaced during flood such as reptiles may migrate to densely populated areas and cause much havoc.
Sea level rise, coral bleaching, ocean acidification, ocean warming, and rising carbon dioxide levels are all examples of how climate change in Sri Lanka might affect the biodiversity of the coastal ecosystem. Coral reefs bleach as a result of high temperatures, and most marine creatures rely on them for food and shelter. The coral reef community may suffer as a result. Warm water also has the potential to modify ocean currents, migration patterns, and shift feeding areas away from typical nesting grounds. Reef fish and sea turtles are also harmed by warm water. When the ocean gets too warm, corals that produce reefs and algae that live inside corals can’t survive. The coral is left with a bleached appearance due to the loss of algae, which causes starvation. The ocean absorbs carbon dioxide (CO2), a greenhouse gas that contributes to climate change, altering the ocean’s pH balance, making it more acidic and toxic to some sea creatures like shellfish and corals5.
Animals are unable to adapt to and respond to these rapid environmental changes. Climate change reduces the distribution and number of species, potentially leading to extinction, especially for endemic species. As a result, this has a significant influence on wildlife and may become the most serious issue in the near future.