English Olympiad Class 8 - Sample paper 03

Passage 1 - Methane Leaks from Seabeds

You know that methane (CH4) is a greenhouse gas that is emitted during the production and transport of coal, natural gas, and oil. Its emissions also result from livestock and other agricultural practices, and by the decay of organic wastes in municipal solid wastes landfills. But, did you know that the gas also leaks from seabeds, too? Yes, at least in some areas on the Atlantic coast of the USA.

Scientists believe that methane stored under the seabed is one of the largest reserves on the planet. They have identified hundreds of ‘seeps’ along the American Atlantic coast—places where gas bubbles out of the sea floor— and believe that “tens of thousands” more seeps to be lying undiscovered. You would be surprised that seabed methane ‘seeps’ are not a new phenomenon. Scientists claim that they have continued for over 1000 years!

Some experts believe that climate change could cause huge quantities of methane to be released from the Arctic seabed and the others who believe that evidence, that suggests these underwater emissions have increased. While, it is likely that as global temperatures rise, more methane will be emitted from such seafloor reservoirs, most of the scientists doubt the amount released will be big when compared to other natural sources.

This research has two important implications. First, it leads scientists to wonder where else such leaks maybe going on or may occur in the future. In case, these seafloor emissions are significantly high, they could radically change calculations of natural carbon emissions, scientists fear.

Secondly, undersea methane seeps could have serious implications for marine life. Since, methane increases the acidity of seawater and reduces its oxygen content of seawater; even small changes in acidity can interfere with the shell formation in small marine creatures, the foundation of ocean food webs. So, any impact on them will, in turn, have an indirect effect on other things.

So, while the research doesn't suggest a huge increase in methane emissions to the atmosphere, the wider impacts of these findings may have significant implications for the world's oceans nonetheless. For example, the gas originating from these reservoirs could trigger a rat race among oil companies to determine whether they can be tapped for oil and natural gas.

Passage 2 - Flying fish

Flying fish can be seen jumping out of warm ocean waters worldwide. Their streamlined torpedo shape helps them gather enough underwater speed to break the surface, and their large, wing-like pectoral fins get them airborne.

Flying fish are thought to have evolved this remarkable gliding ability to escape predators, of which they have many. Their hunters include mackerel, tuna, swordfish, marlin, and other larger fish. For their nutrition, flying fish feed on a variety of food, including plankton, bacteria, and other tiny marine creatures. The average lifespan of flying fish is around five years in the wild. In size, they can grow up to 18 inches. There are about 40 known species of flying fish. Beyond their useful pectoral fins, all have unevenly forked tails, with the lower lobe longer than the upper lobe. Many species have enlarged pelvic fins as well and are known as four-winged flying fish.

The process of taking flight, or gliding, begins by gaining great velocity underwater, about 37 miles (60 kilometers) per hour. Angling upward, the four-winged flying fish breaks the surface and begins to taxi by rapidly beating its tail while it is still beneath the surface. It then takes to the air, sometimes reaching heights of over 4 feet (1.2 meters) and gliding long distances, up to 655 feet (200 meters). Once it nears the surface again, it can flap its tail and taxi without fully returning to the water. Capable of continuing its flight in such a manner, flying fish have been recorded stretching out their flights with consecutive glides spanning distances up to 1,312 feet (400 meters). Flying fish can soar high enough that sailors often find them on the decks of their ships.

Flying fish swim in large schools (groups) and are attracted to light, like a number of sea creatures, and fishermen take advantage of this with ample results. Canoes, filled with enough water to sustain fish, but not enough to allow them to propel themselves out, are affixed with a luring light at night to capture flying fish by the dozens. There is currently no protection status on these animals.

Passage 3 - Solar Energy

Solar energy is a sustainable and renewable source of power that harnesses the energy from the sun to generate electricity. The process involves using photovoltaic cells, commonly known as solar panels, which convert sunlight into electrical energy. This clean and green energy solution has gained popularity as a viable alternative to traditional fossil fuels.

One of the key advantages of solar energy is its environmental friendliness. Unlike conventional power sources, solar power generation produces no harmful emissions or pollutants, contributing to a reduction in greenhouse gases. Solar panels are low-maintenance, with minimal negative impacts on ecosystems compared to other energy-producing methods.

Another benefit is the potential for decentralized power generation. Solar panels can be installed on rooftops or in remote areas, providing electricity to communities that may not have access to a centralized power grid. This aspect of solar energy promotes energy independence and resilience.

However, challenges such as intermittency and energy storage need further advancements for widespread adoption. Despite these hurdles, ongoing research and technological developments continue to enhance the efficiency and affordability of solar energy systems, making them an integral part of the global push towards sustainable energy solutions.