What is “abrupt climate change?
The term “abrupt climate change” describes changes in climate that occur over the span of years to decades, compared to the human-caused changes in climate that are occurring over the time span of decades to centuries. From ice cores, ocean sediments, tree rings, and other records of Earth’s past climate, scientists have found that changes in climate have occurred quickly in the past—over the course of a decade. An example of an abrupt climate change event is the Younger Dryas (~12,000 years ago), a period of abrupt cooling that interrupted a general warming trend as Earth emerged from the last Ice Age. During the Younger Dryas period, average summertime temperatures in New England cooled by about 5-7°F (3-4°C). This and other abrupt events have been linked to changes in an ocean circulation pattern known as thermohaline circulation.
The term “abrupt climate change” describes changes in climate that occur over the span of years to decades, compared to the human-caused changes in climate that are occurring over the time span of decades to centuries. From ice cores, ocean sediments, tree rings, and other records of Earth’s past climate, scientists have found that changes in climate have occurred quickly in the past—over the course of a decade. An example of an abrupt climate change event is the Younger Dryas (~12,000 years ago), a period of abrupt cooling that interrupted a general warming trend as Earth emerged from the last Ice Age. During the Younger Dryas period, average summertime temperatures in New England cooled by about 5-7°F (3-4°C). This and other abrupt events have been linked to changes in an ocean circulation pattern known as thermohaline circulation.
There is an abundance of scientific evidence that shows major and widespread climate changes have occurred with startling speed. For example, roughly half of the warming of the North Atlantic Ocean –>North Atlantic Ocean since the last ice age was achieved in only a decade, and this warming was accompanied by significant changes in climate across most of the globe. Research over the past decade has shown that these abrupt – or nonlinear – climate changes have been especially common when the climate system was being forced to change most rapidly. Thus, the rate of buildup of carbon dioxide –>carbon dioxide in the atmosphere may increase the possibility of large, abrupt and unwelcome regional or global climate events. The mechanisms of past abrupt climate changes are not yet fully understood, and climate models typically underestimate the size, speed and extent of those changes. Hence, future abrupt changes cannot be predicted with confidence. Yet, because of greenhouse warming and oth
