A number of things go into making our planet Earth a habitable place, and when everything is in balance, we, its habitants, thrive along with it. But the only planet that we can call home, is in danger of being obliterated because we have not been taking care of it.
The Earth has a climate system that is comprised of five interacting parts, the atmosphere (air), hydrosphere (water), cryosphere (ice and permafrost), biosphere (living things), and lithosphere (earth's crust and upper mantle). The system receives nearly all of its energy from the sun, with a tiny amount from the earth's interior, and the balance of incoming and outgoing energy and the passage of the energy through the climate system determines the outcome.
Based on the interaction between the various components, we can either have a positive or a negative climate change, and they can lead to warming or cooling of the Earth's surface. But both can happen due to human activities too, and presently we humans are driving climate change through global warming.
Global warming refers to the long-term rise in the average temperature of the Earth's climate system, and though it is known to have happened before, it has been observed that changes since the mid-20th century have been much greater than those seen in previous records.
The effects of global warming can already be seen, and the largest human influence has been the emission of greenhouse gases such as carbon dioxide, methane, and nitrous oxide.
Global warming has led to a number of things like rising sea levels, regional changes in precipitation, more frequent extreme weather events such as heatwaves, and expansion of deserts. The rising of surface temperature and its effects can be witnessed more in the Arctic, where the retreat of glaciers, permafrost, and sea ice is greatly visible, which in turn is leading to the extinction or relocation of many species as their ecosystems change.
Slowly but surely it will diminish crop yields and harm food security, and it is already affecting many coastal cities, as with the rise in seawater, many of the places are being submerged in water. Overall, higher temperatures bring more rain and snowfall, but for some regions droughts and wildfires increase instead.
The effect is seen not only on land, but in the sea as well, with coral reefs, which are often called "rainforests of the sea", being affected by the rising temperatures, excess nutrients (nitrogen and phosphorus), oceanic acidification, overfishing, sunscreen use, and harmful land-use practices like runoff from chemical factories. Coral reefs are an important part of the ecosystem, and if they disappear, the effect will be on tourism, fisheries and shoreline protection.
The recent wildfires in the Amazon rainforest have led to environmentalists fearing loss of biodiversity and also the release of the carbon contained within the vegetation, which could accelerate global warming. The climate system has a large "inertia", and with greenhouse gases persisting in the atmosphere, the climatic changes and their effects will continue for many centuries even if greenhouse gas emissions are stopped.
FIGHT AGAINST CLIMATE CHANGE:
World leaders are waking up to the devastating effects of global warming, and as of 2019 most have agreed to the United Nations Framework Convention on Climate Change (UNFCCC), but some countries have not. The objective of the Convention is to prevent dangerous human interference with the climate system. As of September 2019, nine countries have made climate emergency declarations.
Where scientific consensus on climate change is concerned, there is an overwhelming agreement that global surface temperatures have increased in recent decades and that the trend is caused mainly by human-induced emissions of greenhouse gases. In 2018 the IPCC published a Special Report on Global Warming of 1.5 °C which warned that, if the current rate of greenhouse gas emissions is not mitigated, global warming is likely to reach 1.5 °C (2.7 °F) between 2030 and 2052, risking major crises. The report said that preventing such crises will require a swift transformation of the global economy that has "no documented historic precedent".
The global warming problem came to international public attention in the late 1980s, and while it was not viewed as an emergency immediately, people have now started taking it seriously. There have been worldwide protests with many calling for fossil fuel divestment and investment in climate solutions.
The protests have also been taken up by school students, who take time off from class to participate in demonstrations to demand action to prevent further global warming and climate change. The movement had started after Swedish schoolgirl Greta Thunberg staged a protest in August 2018 outside the Swedish Riksdag (parliament). The movement focused on three demands - 100 per cent clean energy, keeping fossil fuels in the ground, and helping climate refugees.