Why are climate change and global warming serious problems?

Climate is always changing and it appears that earth has warmed and cooled throughout history. How is the recent change different than changes in the past and why should these worry us?

The main reason for worry about the current climate change is that it is happening too fast for our comfort.

While global warming (and global cooling) could have been happening for millions of years, sometimes in cycles, there’s been an alarming acceleration in the recent past – the rate of change has increased considerably.

Let’s consider global warming and the attendant temperature changes. The biggest temperature swings our planet has experienced in the past million years are during the ice ages. Based on data models, scientists estimate that after ice ages had ended in the past, it had taken about 5,000 years for the planet to warm between 4 and 7 degrees Celsius. Compare this with the warming in the past century — 0.75 degrees Celsius in surface temperature. That is, int he past century, the atmosphere has warmed roughly eight times faster than the warming after the ice age.

Even within the last 100 years, about two thirds (0.5^OC) of the increase has occurred between 1975 and 2015 – about 0.13^OC per decade for the period. Between 1915 and 1975, the total change in temperature was about 0.25 deg C – about 0.04 deg C per decade for the period! Thus, even within the past century, the rate of change in the last forty years has been thrice compared to that in the first sixty!

All these rapid changes to climate can result in the following stuff that you may not want to hear about:

• Higher Temperatures – Earth’s temperatures recently have been the hottest ever recorded. Why does this matter? Because a change of even 1 degree Fahrenheit – which may sound small – can upset the delicate balance of ecosystems, and affect plants and animals that inhabit them.
• Rising Seas – As ocean waters warm, they expand, causing sea-levels to rise. Melting glaciers compound the problem by dumping even more fresh water into the oceans. Rising seas threaten to inundate low-lying areas and islands, threaten dense coastal populations, erode shorelines, damage property and destroy ecosystems such as mangroves and wetlands that protect coasts against storms.
• More Storms, Droughts, and Floods – Climate change is intensifying drought, storms, and floods around the world. Where nature has been destroyed by development, communities are at risk from these intensified climate patterns. Scientists around the world are studying how nature can be a buffer for these intensified weather patterns, and TNC is working with leaders and communities to implement solutions that make a difference for nature and people.
• Communities at Risk – Hundreds of millions of people (possibly over a billion) worldwide live within a few feet of sea level. Sea level rise associated with climate change could displace a good percentage of these people in low-lying areas – especially in developing countries. Inhabitants of some small island countries that rest barely above the existing sea level are already abandoning their islands, some of the world’s first climate change refugees. In fact, in May 2016, the residents of Isle de Jean Charles were given $48 million to move – the first U.S.-based climate refugees.
• Risk to Landscapes and Wildlife – Rising temperatures and changing patterns of precipitation are changing where plants grow, and in the case of our oceans, encouraging the proliferation of species that impact native ocean habitat. As landscapes and habitats literally shift, wildlife must quickly adjust. Experts predict that one-fourth of Earth’s species will be headed for extinction by 2050 if the warming trend continues at its current rate.
• Economic Risks – The true economic impact of climate change is hard to predict. But it’s safe to say that many key economic sectors – from fishing to energy to water utilities – will feel long-term impacts of climate change. As we move into an era in which climate change impacts are all around us, adapting to these changes quickly will be key for all sectors of the global economy.