As per the Paris Climate Agreement, the UN and world leaders are working towards carbon neutrality. The reason for this is to prevent global warming. According to studies done by various experts sometime in the mid 1800s, our planet will start experiencing doomsday symptoms if global temperature is 4 degree Celsius above pre-industrial era global temperature.
These studies were conducted after scientists discovered a rise of global temperature following industrialisation during the second half of the 1800s. While they all acknowledged that the critical threshold is 4 degrees above pre-industrialisation era, they also agree that they should set a lower threshold target rather than use the 4 degree threshold as a target. Thus they decided to set the target threshold at 1.5 degree Celsius.
According to their studies, they estimate that in order to keep global warming below 1.5 degrees, the world needs to achieve carbon neutrality by 2050 at the latest. We are at 1.30+ degrees today, and most agree that we are running out of time. Hence, this is the ultimate objective of the E in ESG.
It is also worth noting that they are calculating global temperature based on change in enthalpy, and therefore there is no base temperature to refer to when talking about 1.5 or 4 degrees. Enthalpy is a thermo-dynamics concept, whereas Enthalpy = internal energy plus (pressure x volume). However, in practice, we never calculate actual enthalpy. Rather we calculate the difference of enthalpy.
To make this easier to understand, take the total volume of seawater on our planet. It is unfeasible to calculate the actual volume of sea water on our planet, but we can calculate the difference of volume of seawater. For example, if we pour 100 L of seawater into the ocean, we know there is a difference of +100 L of seawater in the ocean, without knowing the total volume of seawater. Enthalpy works the same way, and this is how we are measuring global temperatures. Calculating the difference without knowing the base temperature of our planet. Trying to calculate actual global temperature is an endeavour that is too expensive and complicated to attempt with current technology.
