Global Warming and Climatic Change | Botany Optional for UPSC PDF Download

Introduction

In recent times, an unprecedented heatwave has swept across several European countries, while certain Asian nations, including China, have grappled with the most severe deluge of modern times. These extreme events serve as stark reminders of the ever-growing global warming and climate change crisis. The repercussions of these environmental shifts are far-reaching, prompting major countries worldwide to unite in their efforts to combat these issues. Initiatives such as the Paris Agreement and the International Solar Alliance have been established to address these concerns head-on.

Global Warming and Climate Change

Global Warming

• Global warming is the gradual elevation in the Earth's average surface temperature due to the greenhouse effect.
• It signifies the slow increase in the Earth's mean temperature over time.
• The primary cause of global warming is an intensified greenhouse effect.
• Major greenhouse gases responsible for global warming encompass carbon dioxide (CO₂), methane (CH₄), nitrous oxide (N₂O), sulfur hexafluoride (SF₆), hydrofluorocarbons (HFC), and perfluorocarbons (PFC).

The Greenhouse Effect

• The greenhouse effect is a natural process responsible for heating the Earth's surface and atmosphere.
• It entails the retention of solar energy within the Earth's atmosphere, gradually re-radiating heat and acting as a thermal covering around the planet.
• This natural greenhouse effect is essential for maintaining Earth's temperature within a range suitable for life.
• Without this effect, the Earth's surface would be much colder, at approximately -18°C, instead of the current average of 15°C.
• Key greenhouse gases, such as carbon dioxide, methane, and water vapor, absorb and re-emit infrared radiation from the Earth's surface, contributing to this warming phenomenon.

Climate Change

• The current climate conditions, experienced over the past 10,000 years with minor fluctuations, are the predominant climate pattern.
• Earth's climate has undergone various shifts and alterations throughout its history.
• Climate change arises from multiple factors, including population growth, natural occurrences, terrestrial influences, biodiversity loss, and notably, global warming.