What is the PLEES index?


The news is filled with stories of the climate changing. It talks about goals and different scenarios to aim for or avoid at all costs. But what do all these numbers and letters mean? How would life chhange if global temperatures raise by 2°C? Then what about 8°C?


Maslow (1943) argued that human motivation is driven by needs and identified five levels of human needs, arranged hierarchically. These levels can be represented in a pyramid. The lowest level includes the basic or physiological needs, such as breathing or feeding oneself. Once these primary needs have been satisfied, one gradually moves up the pyramid to the highest level, representing the possibility to achieve personal satisfaction and fulfillment. Using the representation of his hierarchy as a pyramid, we linked each level of the pyramid to an index. The mapping is schematically shown in this figure, with the Maslow's pyramid of needs depicted on the left side, going from the most basic physiological needs to higher level self-fulfillment needs. The corresponding pyramid on the right illustrates the quantifiable and measurable quantities that we use to construct the PLEES index.


Maslow's pyramid of needs.
The PLEES pyramid.

The PLEES index is a tool to help visualise the impact of climate change on different aspects of life. The index is made up of four parts which represent how quality of life will change, namely: Povery rate, Life Expectancy, Employment rate, and life Satisfaction. Let's have a closer look at each of these aspects.


Poverty:


The first letter of the PLEES index stands for Poverty, reflecting the ability to meet basic necessities of life such as eating, drinking, sleeping. This index correlates with dry spells. When there are more dry spells, food security worsens, which leads to more people falling into precarious conditions.



Life Expectancy:


The second set of letters in the index stands for the Life Expectancy in a country. The life expectany is influenced by a whole array of effects. With regards to climate change, the number of extreme heat days has the strongest effect. During heat waves the risk of premature death increases thereby reducing the life expectancy.



Employment:


The third part of the PLEES index is Employment. Many crucial industries, such as agriculture and construction, are strongly dependent on the climate. On a warming planet, the number of working hours lost due to heat increases, which is reflected in this index.



Life Satisfaction:


The last letter of PLEES stands for the life Satisfaction in a country. Based on literature studies life satisfaction depends on the gross domestic product of a country and a climate variable that measures how much our houses have to be heated or cooled to feel comfortable indoors year-round.



What is the PLEES index based on?


The PLEES index is based on research from various fields publised peer-reviewed articles. Each of these articles demonstrates the correlation between one of the factors of the index and an aspect of the climate. These methods are explained in detail on the Our Project page. All used data is also cited on the Sources page.



Where can see the PLEES index of my country?


On the Map page you can see the PLEES index for each country as well as different scenarios. On this page you can also see several graphs to help you interpret the different aspects of the index.