Category: Uncategorized

According to an Associated Press video, President Biden accused China of “not showing up” at the COP26 Climate Summit in December 2021 despite wanting to be a world leader. “It just is a gigantic issue and they walked away. How do you do that and claim to be able to have any leadership?” Biden said.… Continue reading Fighting Climate Change China’s Way—Paul Chan

Wealthy countries often make the argument that as the entire planet is coming under climate change threats, the whole of humanity must equally shoulder the burden of fighting climate change. This argument ignores three brutal facts. First, a handful of developed economies have contributed the lion’s share to actual and projected warming. According to the… Continue reading Climate Challenges of Developing Countries—Paul Chan

The Intergovernmental Panel on Climate Change (IPCC) report issued in February 2022 paints a dire future for the human race. Recorded global temperatures have already risen by 1.1 degrees Celsius (2 degrees Fahrenheit) since the Industrial Revolution. At the Paris Climate Summit in 2015, world leaders have vowed to limit warming to no more than… Continue reading Climate Migration has Begun—Paul Chan

Some people say climate change does not discriminate. But it does discriminate against the poor in big ways. Poverty and climate change are related in two ways. Among all income levels, low income people or countries contribute the least to warming, yet they have suffered and will continue to suffer disproportionately from the brunt of… Continue reading Climate change and poverty—Paul Chan

The weather forecast that you see on TV or on your mobile actually starts with collecting data using satellites, weather radars, and ground and upper-air in situ measurements. Weather forecast is an initial value problem. To produce a forecast, a numerical weather prediction model processes today’s weather observations (hence the name initial value) based on… Continue reading If we can’t predict weather beyond two weeks, how can we claim to predict climate fifty years from now? –Paul Chan

Systematic observation of the climate system is carried out by national meteorological agencies under the coordination of UN’s World Meteorological Organization (WMO). These national agencies take measurements at standard preset times and places, monitoring the atmosphere, ocean, and terrestrial systems. Since national monitoring systems all form part of a global network, it is vital that… Continue reading How is climate being monitored?–Paul Chan

Most of the global carbon emissions are used to support lifestyles of the world’s higher income population. An earlier blog post “Carbon inequality—the economic divide in greenhouse gas emissions” (https://understandclimate.com/?p=123) states: “The UN 2020 Emissions Gap Report presents a picture of worldwide carbon inequality… In 2015 the richest 1% of the world population emit 15% of the… Continue reading Our lifestyles are determining the future of humankind—Paul Chan

An earlier post has discussed the role of Arctic snow/ice feedback on climate. This post will extend the subject of feedback effects to other parts of the climate system. The feedback effect we are most familiar with is perhaps the acoustic feedback. The electric circuit connecting a microphone to a speaker passes through an electronic… Continue reading The roles of positive feedbacks in climate change—Paul Chan

Two recent peer-reviewed articles in the Journal Nature Food show that previous measures of the food-system’s contributions to greenhouse gas (GHG) emissions had been underestimated. (https://www.nature.com/articles/s43016-021-00225-9; https://www.nature.com/articles/s43016-021-00358-x) One study finds that, in 2015, food-system emissions amounted to 18 Gt CO2 equivalent per year globally, representing 34% of total emissions. Within the food system, the largest proportion came… Continue reading How does our diet affect climate change?—Paul Chan

Electric vehicles have zero tailpipe emissions, but still have emissions associated with manufacturing and usage. Here we present estimates for lifecycle (manufacturing and operations) emissions of battery electric vehicles (BEV) and internal combustion engine vehicles (ICEs). This information is based on a Bloomberg NEF report. The report considers the lifetime average carbon intensity of the… Continue reading Carbon footprint of electric vehicles—Paul Chan