Returning the Earth’s Call: Overview of Centuries

The first earth day was established in April 1970 as the UNESCO initiative to honor the Earth. Our history recorded a transformative way people lived and worked triggered by the industrial revolution started around 1850. This period reshaped the global economy, which has brought social and environmental changes ever since. Modern industry came in one package with a higher emission of greenhouse gases. The research from Our World in Data suggests that the annual emission of CO2 significantly indicated in early 1900 at around 5 billion tons. At the end of 19 century, the emission was 4-fold times and spiking these days to around 35 billion tons. Amstrong McKay et al. (Science vol. 377, 8811, 2022) warned that this CO2 emission contributes to the temperature rise, arctic surface decline, and sea level rise. Since 1970, the temperature has risen about 0.9C, according to the NASA global surface temperature report by 2021. The Arctic Sea ice has melted at about a rate of 13% decline per decade. Currently, the sea level has risen 12 centimeters higher per decade, according to CSIRO. A positive change is also evident in several actions taken after Earth Day 1970. The US Clean Air Act encourages the automotive industries to redefine their combustion technology. Although an increase of more than 37% of energy is utilized, the pollutants have decreased by about 78%, according to the EPA. New cars, trucks, and buses are 99% cleaner by utilizing today's tailpipe technology. The use of cleaner fuel, such as unleaded gasoline, has resulted in a 95% decrease in the level of lead in children's blood. In 1987, every country in words joined the Montreal Protocol to ban CFCs. Technology today allows us to reduce ozone-depleting emissions by up to 99%. According to the UN projections, by 2050, the ozone layer is expected to return to its 1980 level. The ozone layer has stabilized and started to recover, thereby preventing an estimated 2 million cases of skin cancer per year. In 2015, 197 countries have signed the Paris agreement which is the world's most ambitious effort to tackle climate change. All countries agreed to reduce carbon emission dramatically and to zero by 2050. Many efforts have been made to switch rapidly to renewables, conserve and restore forest and grassland, and protect coastal and ocean environments. The preservation of forests and wetlands will not only conserve biodiversity but also secure the carbon in trees and soil. Here, everyone has a role to play, including us as scientists, engineers, or civil society.