Exceeding the 1.5 degrees Celsius (°C) temperature limit, even temporarily, can have several potential impacts on the environment, ecosystems, and human societies. While the Paris Agreement set a target to limit global warming to well below 2°C above pre-industrial levels and pursue efforts to limit the temperature increase to 1.5°C, it's important to note that the Earth's average temperature has already risen by about 1.1°C since the pre-industrial era. Here are some potential impacts of surpassing the 1.5°C limit:
Extreme weather events: A warmer climate can lead to an increased frequency and intensity of extreme weather events such as heatwaves, droughts, floods, hurricanes, and storms. These events can result in significant damage to infrastructure, agriculture, and human settlements.
Sea-level rise: As temperatures rise, glaciers and ice caps melt, causing sea levels to rise. Exceeding the 1.5°C threshold can accelerate this process, leading to the displacement of coastal populations, loss of land, and increased vulnerability to coastal erosion and flooding.
Ecosystem disruption: Many ecosystems are highly sensitive to temperature changes. Beyond 1.5°C, there is an increased risk of irreversible damage to ecosystems such as coral reefs, tropical rainforests, and Arctic ecosystems. This can result in biodiversity loss, species extinction, and disruption of crucial ecological services.
Impacts on agriculture and food security: Rising temperatures, changes in precipitation patterns, and increased frequency of extreme weather events can adversely affect agricultural productivity. Crop yields may decline, leading to food shortages, increased food prices, and potential social and political instability.
Water scarcity: Higher temperatures can exacerbate water scarcity issues in many regions. Changes in precipitation patterns can lead to droughts, reduced water availability, and increased competition for water resources, impacting agriculture, industry, and human populations.
Public health risks: Climate change can have adverse effects on public health. Increased temperatures can lead to heat-related illnesses and deaths, as well as the spread of vector-borne diseases like malaria and dengue fever. Disruptions to ecosystems can also impact disease vectors and food-borne illnesses.
Social and economic consequences: The above impacts can have far-reaching social and economic consequences. Displacement of communities due to sea-level rise, increased frequency of extreme events, and food insecurity can lead to conflicts, migration, and economic instability.
It's important to note that these impacts are not absolute thresholds but rather represent a continuum of risks and vulnerabilities. Even temporarily exceeding the 1.5°C limit can have long-lasting consequences, and concerted efforts to mitigate climate change and reduce greenhouse gas emissions are crucial to minimize these risks and protect our planet.