Editorial 1: The threat of rising sea levels
Context
- The World Meteorological Organisation (WMO) has published in a report entitled ‘State of the Global Climate 2022’ which states that the world’s sea level is rising at an unprecedented rate, portending potentially disastrous consequences for the weather, agriculture, the extant groundwater crisis, and social disparities.
Details of the Report
- Along with accelerating sea-level rise, it focused on a consistent rise in global temperatures, record-breaking increases in the concentration of greenhouse gases as well as glacier loss, sustained drought-like conditions in East Africa, record rainfall in Pakistan, and unprecedented heatwaves that struck Europe and China in 2022.
- It also stated that droughts, floods and heat waves affected communities on every continent and cost many billions of dollars.
- Antarctic sea ice fell to its lowest extent on record and the melting of some European glaciers was, literally, off the charts.
| Sea level rise is an increase in ocean depth brought on by climate change, particularly global warming, and is primarily caused by three things: thermal expansion, glacier melting, and the loss of Greenland and Antarctica’s ice sheets. Tide stations and satellite laser altimeters are the main tools used to measure sea level. |
GSML and the data
- The rate of global mean sea-level [GSML] rise has doubled between the first decade of the satellite record and the last.
Factors
- The WMO report points to the following factors as being responsible for a rising GSML. The report also quantifies the individual contribution of these factors to yield, what researchers call the “GSML budget”.
- According to the 2005-2019 report , loss of glaciers and ice sheets contributed 36% to the GSML rise. Ocean warming — the phenomenon of rising mean ocean temperatures — contributed 55%, and changes in the storage of land water contributed less than 10%.
- As increasing concentrations of carbon dioxide and other greenhouse gases drive global warming, 90% of the ‘extra’ heat is stored in the oceans. This leads to ocean warming.
- And as the ocean heats up, it undergoes thermal expansion, which in turn leads to a rise in the GSML. One measure of ocean warming is the ocean heat content (OHC). OHC measures in 2022 touched a new record.
- The report also says that the earth’s ice cover, known as the cryosphere, has thinned. The cryosphere includes the Arctic and Antarctic regions glaciers, the ice sheets of Greenland and Antarctica seasonal snow cover, and permafrost.
Problems with sea- level rise
- The accelerated pace will cause changes in land cover and rising seas swallow more of the land cover, particularly in coastal areas, coastal communities will face an acute shortage of land for human use. This land crunch will lead to an increase in social disparities between people living in coastal areas.
- As the GSML continues to rise, along with a rise in ocean temperatures, the chances of cyclones could increase, affecting coastal communities and leading to large economic liabilities for tropical countries such as India and South Africa, which have high population densities.
- As the GSML continues to rise, more sea water could seep into the ground, leading to the groundwater — which is usually freshwater — turning more and more saline. This, in turn, can exacerbate water crises in coastal areas as well as agriculture in adjacent regions.
Sea-level rise affecting societies
- The coastal ecosystems could be completely changed. For example, in the Sundarbans delta in West Bengal, the world’s largest mangrove area, rising sea levels and coastal erosion, due to loss of land and sediment from coastal areas, has left more islands submerged under water, and that, in turn, has forced members of local communities to migrate.
- Since the lives of coastal communities, including their economic activities, is tied intricately with the coastal ecosystem, changes in the coastal ecosystem will further endanger the socio-economic stability of these communities.
Conclusion
- While the sea-level rise is one of several compounding disasters, it also merits individual attention for the unique crises it can precipitate, especially for coastal areas, the communities there that depend on life in the sea, and its ability to render the loss of land.
Editorial 2: Darwin must stay in Indian school textbooks
Context
- Recently in 2023, National Council of Educational Research and Training (NCERT) dropped Darwin’s theory from the examination syllabus of students in the academic year 2021-22.
Need for Darwin’s theory
- As one of the most firmly established theories in science, Darwin’s theory not only explains the origin of human beings and all other forms of life in the world, but also rescues this explanation from the belief that an intelligent designer (God) built them the way they are and put them in their place. Depriving students of this information, especially those who do not take up biology after Class 10 is, as dissenting scientists and educators have pointed out, to be dangerous.
- Darwin’s theory is based on the fossils he collected and the wildlife he observed on his five-year trip (1831-36) on the HMS Beagle, where he also read the book of Charles Lyell- ‘Principles of Geology’.
- Lyell, having studied glaciers, volcanoes and fossils, proposed the concept of gradual geological change that geological phenomena and objects today result from minute changes accumulating over a period of time, much like how random mutations that confer advantage to certain organisms accumulate over time, giving rise to their present-day species.
(An example of how evolution by natural selection works)
Other influences
- Philosopher Bertrand Russell has written about how Darwin’s theory was essentially an extension to the animal and vegetable world of laissez-faire economics.
- The term, conceived by economist Adam Smith and developed by Thomas Malthus, referred to self-interest and free competition in the marketplace.
- Malthus also propounded a theory of population in 1798, where he claimed that humans compete for limited resources until a catastrophic event leads to a decline in their population.
- Darwin held that only those living beings survive that carry variations that give them an edge over others — a phenomenon that he termed as evolution by natural selection.
- Herbert Spencer’s idea of survival of the fittest proposed in 1864, coalesced eventually into a philosophy called social Darwinism which is well known to have fuelled the eugenics movement in the late 19th century.
A reminder about the world of science
- Students and teachers in school must concern themselves with these aspects of Darwin’s theory. Because these examples carry crucial insights about science in both the historical and contemporary world.
- These examples remind us that science is a messy affair that requires caution alongside curiosity, creativity and imagination. If the strength of science lies in its ability to stand the test of critical inquiry, then science classrooms must inculcate the embracing of critique, sometimes at the risk of confronting its own troubled history.
Conclusion
- The teaching of Darwin’s theory offers possibilities of this confrontation without underplaying its strengths. Thus, while Darwin must remain in our textbooks, how we teach him must change.
