The recent spate of deadly tornadoes in the U.S. and the carnage of Typhoon Haiyan in the Philippines are poignant opportunities for us to reflect on the future of civilization. These events are tangible reminders of the sometimes intangible reality of human existence in the anthropocene. Extreme weather affords an opportunity to come to terms with the evidence that shows how human activities are degrading the Earth's ecosystems.
While it is difficult to attribute any individual extreme weather event to global warming, when looked at over time, we see an interesting pattern emerge.
According to the Federal Emergency Management Agency (FEMA), from 1953 to 1983, the U.S. Averaged 26.65 disasters per year. In the last 29 years, the average number of U.S. disasters has risen to 91.4 per year, representing an increase of more than 240 percent.
According to NASA’s Earth Observatory, whether or not global warming is responsible for this increase in natural disasters, it does speak to our future. As stated in the Earth Observatory website, climate change will impact future catastrophes, “changes in climate not only affect average temperatures, but also extreme temperatures, increasing the likelihood of weather-related natural disasters.”
The intense thunderstorms that swept across the U.S. Midwest on Sunday are yet another warning calling us to deal with climate change. This storm follows on the heals of the devastating Typhoon that recently wreaked havoc in the Philippines.
On Sunday, November 17th, a large number of violent thunderstorms and as many as 77 tornadoes touched down in 12 U.S. states. These events killed at least 8 people, wounded many others and left a trail of destruction. Entire towns have been decimated and scores of homes have been wiped off the face of the earth. As terrible as this is, it is nothing compared to Typhoon Haiyan which has killed between four and ten thousand and rendered four million people homeless.
Scientists like Professor Will Steffen, a researcher at the ANU and member of the Climate Council, have linked Typhoon Haiyan to climate change, others describe it as being exacerbated by global warming. The relationship between tornadoes and climate change is more complex and harder to predict than hurricanes (typhoons, cyclones).
Understanding convective available potential energy, (CAPE) may offer us insights into the relationship between tornadoes and climate change as this measure represents the energy that powers storms. It is determined by the combination of moisture and temperature differences between the ground and higher regions of the atmosphere. It is known that global warming leads to an increase in CAPE and this in turn leads to an increase in thunderstorms which can spawn tornadoes.
The relationship between global warming and tornadoes was discussed in a 2007 Scientific American interview with climate scientist Kevin Trenberth of the National Center for Atmospheric Research in Boulder, Colorado. While he predicted more hurricanes due to global warming he also suggested there may be an impact on tornadoes.
"Of course, tornadoes are very much a weather phenomenon. They come from certain thunderstorms, usually supercell thunderstorms that are in a wind shear environment that promotes rotation," Trenberth said. "The main climate change connection is via the basic instability of the low-level air that creates the convection and thunderstorms in the first place. Warmer and moister conditions are the key for unstable air. The oceans are warmer because of climate change."
Grady Dixon, an associate professor of geosciences at Mississippi State University who studies tornado climatology also weighed in on the connection between tornadoes and global warming. "The most common finding is a warming environment leads to more storms and more intense storms." Paradoxically, Dixon also pointed out that a warming climate means warmer temperatures in the north which should decrease wind shear and may lead to fewer tornadoes.
Harold Brooks of the National Weather Center recently talked about a condensing effect, meaning more tornadoes could occur on fewer days of the year. Jeff Trapp, a professor of atmospheric science at Purdue University said the tornado season may be expanded by a warming world. "We would see an increase in the number of days that could be favorable for severe thunderstorm and tornado formation," he said.
Trapp also said that the "CAPE increases with time in a globally warmed world, mainly because the temperature near the ground and lower parts of the atmosphere increases and becomes more humid...In a globally warmed future world, that thunderstorm should be more intense."
Applied environmental geoscience major Derrek Davey said the devastation from the storms has a lot to do with global warming.
“We have measured that we have increased our global temperature 1 degree. This does not seem like much, but it is a huge factor with ice caps melting. More water equals . . . more devastation from storms.”
We know that storms and weather-related events are clearly connected to temperature. “So it should not be a big surprise to find that the rapid average global warming we’ve seen since the Industrial Revolution would affect them.” said Alice Mulder, chair of the Environmental Issues Committee. “[G]lobal warming does change the base conditions that make some of these events more likely.”
It is important to note that the exact relationship between climate change and tornadoes is still not very well understood. Scientists do not know how global warming will impact the frequency or intensity of tornadoes. However, the absence of evidence does not mean evidence of absence.
In 2011, the U.S. suffered through 1,700 tornadoes which is the second-deadliest tornado season in history. But 2012 and 2013 did not see elevated numbers of tornadoes. However, just as looking at one extreme weather event does not prove or disprove climate change, looking at tornado data over the course of a few years does not necessarily contradict the notion that there is a trend.
Over the course of a few years we can expect to see some variability, science looks at weather trends over much larger time frames. While the nature of science will always entertain a degree of uncertainty, more than 95 percent of climate scientists are in agreement about anthropogenic global warming. They also acknowledge that this will have serious implications for the health of the planet.
It remains to be seen whether seas will rise by 3 feet or by 10 feet, we also are not certain if the average global temperature will climb by 4 degrees or by 7. What we do know is that it is getting warmer and seas are rising. We know that warming is related to extreme weather.
We should leave investigation of the details to climate scientists and the public should be focusing on what we do know and its implications for the planet. The relationship between global warming and extreme weather should not be derailed by the few remaining -- albeit powerful – skeptics who try to undermine the veracity of the vast body of climate science by pointing to examples of uncertainty.
These impacts of climate change are catastrophic. This is not some theoretical notion for the distant future, this is a fact here and now. People are already dying due to disease, food shortages, heat waves and air quality. As reported in the Daily Beast, a 2012 Climate Vulnerability Monitor report indicates that global warming is already killing four-hundred thousand people each year.
Anthropogenic climate change adversely impacts the health of humans and many other species of animal and plant life. This is a fact borne out in numerous studies and reports including those published by the United Nations, World Health Organization (WHO) and Environmental Protection Agency (EPA).
In March, Admiral Samuel J. Locklear III, the commander of the United States Pacific Command, told security and foreign policy specialists in Cambridge, Mass., that global climate change is the greatest threat the United States faces — more dangerous than terrorism, Chinese hackers and North Korean nuclear missiles.
Extreme weather events help people to see what climate change looks like. People in the U.S., even those that belong to the Republic party, traditionally a bastion of climate denial, are coming to terms with the veracity of global warming. As reported in the Guardian, a new study from Stanford University's social psychologist Jon Krosnick found that "a vast majority of red-state Americans believe climate change is real and at least two-thirds of those want the government to cut greenhouse gas emissions.
Whether or not Typhoon Haiyan or the tornadoes in the U.S. are directly caused by climate change is not the point. The issue that is highlighted by these phenomenon encourages us to embrace the scientific evidence. We know that extreme weather events are expected to intensify as global warming proceeds.
Violent climatic occurrences are consistent with climate models which predict increasingly severe extreme weather events as the earth warms. While we may not be able to be certain about the attribution of specific weather events, we know the earth is warming, we know that the oceans are rising as well. We also know that a warmer world increases the likelihood of precipitation, storm surges, flooding and extreme weather.
As the Prince of Wales said recently, ‘The devastating impact of Typhoon Haiyan in the Philippines should surely have been a poignant and telling reminder of the intimacy and interdependence of man’s relationship with the natural world."
Despite critics who claim Charles overstated the case, we have good reason to question the ways in which we relate to the planet. Even if we are foolish enough to ignore climate models that predict more extreme weather, we will still be subject to sea level rise and ocean acidification among other adverse affects.
Extreme weather demands that we face the civilization-altering impacts we are having on the planet. The challenge of the Anthropocene forces us to reflect on what it means to be human. This is the great existential question of our times.
To quote the immortal words of Shakespear's Hamlet:
“To be, or not to be: that is the question:
Whether 'tis nobler in the mind to suffer
The slings and arrows of outrageous fortune,
Or to take arms against a sea of troubles,”
We are destroying the Earth upon which all life depends, and we must reconcile ourselves to the implications of our actions. As Roy Scranton commented in the Times, "If we want to learn to live in the Anthropocene, we must first learn how to die."
Regardless of the causal attribution for Typhoon Haiyan and the recent U.S. Tornadoes, it is no exaggeration to say that climate change poses a threat to life on earth. Extreme weather events offer a glimpse into the future and this provides an opportunity for us to reflect on the choice between accepting our impending death or collectively resolving to change our ways.
Richard Matthews is a consultant, eco-entrepreneur, green investor and author of numerous articles on sustainable positioning, eco-economics and enviro-politics. He is the owner of The Green Market Oracle, a leading sustainable business site and one of the Web’s most comprehensive resources on the business of the environment. Find The Green Market on Facebook and follow The Green Market’s twitter feed.
Image credit: Ingo Meironke, courtesy flickr