Meteorologist: climate crisis happening now
Insurers and reinsurers have been told that the climate crisis is the problem of our time, even more so than Covid-19.
Marshall Shepherd, a leading meteorologist, said it was crucial for scientists to make people understand that climate change is happening now and its effects are impacting communities around the world.
He said people inherently understand the risk of floods, tornadoes, and storm surges from hurricanes, but they have a perception that these are one-off events or anomalies.
“As scientists we have to do a better job of conveying that climate change is among us now, it's not some far off thing. Also we have to show the there is risk, that they are probably paying more for health insurance, or their box of cereal at the grocery store, because a drought has impacted wheat productivity,” Dr Shepherd said. He added it was about “connecting the dots to people's kitchen table”.
Dr Shepherd is the director of the atmospheric science programme at the University of Georgia, in Atlanta. He was a keynote speaker at the ILS Bermuda Convergence conference, which was held as a virtual event for the first time this week.
He told delegates that Hurricane Delta, which was tracking towards the southern United States, is the 25th named storm in this year's hurricane season in the Atlantic. He added: “We normally have had about 12 in the Atlantic basin at this time of year.”
Dr Shepherd presented data that showed the last five years rank as the five hottest on record, and were between 0.83 and 0.99 Celsius (about 1.8F) above average.
He said the observed frequency, intensity and duration of some weather events have been changing as the climate system has warmed.
Giving an example of what that this meant for communities and industries, he said Hurricane Michael, in 2018, was so strong it maintained its intensity until it was well inland. In southwest Georgia, which is not on the coast, the hurricane caused more than $2.5 billion of losses to the state's agriculture industry, destroying cash crops including cotton, vegetables, and pecan nuts, and harming timber production. There was also an impact on medical infrastructure, electrical infrastructure, and transportation networks.
Dr Shepherd said the greenhouse effect was vitally important, as it helps life on the planet to survive by not allowing the world to freeze every night, but he added: “We know there is an amplification of the concentration to the greenhouse gases because of human activity.”
A warmer atmosphere could make some locations too heat and humid for people to live comfortably, while some data predicts that sea levels will rise one to two metres by the end of the century due to the melting of ice fields and sea ice, together with the thermal expansion of water.
Warmer oceans fuel storms. As seas become warmer “they have been running on 93-octane instead of 89-octane, if you want to put that in terms of gasoline in a car”, said Dr Shepherd.
He added: “Climate change may mean less hurricanes, but when they do happen they will be stronger. We are seeing that with [hurricanes] Michael, Harvey, Maria, and right now with Delta.
“There is peer-reviewed literature that suggests hurricanes are slowing down when they get closer to the coastline.”
He said an example was Hurricane Dorian, which last year sat over the Bahamas for a day as a Category 4 or Category 5 hurricane.
“We are seeing slower storms, and this is related to the jet stream pattern and the way they move the storms along in our atmosphere,” Dr Shepherd said.
“We are seeing increases in compound dry-hot extremes, which exasperate wildfires, heatwaves, public health risk, and energy use. California saw five of its six largest wildfires on record in the last couple of months, consuming more than 2.2 million acres of land.”
He said attribution science looks to see how much natural occurrences and factors are amplified by human activities, and in that way climate change can be attached to extreme heat events, a lack of cold events, and bouts of extreme drought and heavy precipitation.
When asked what was the most impactful thing people can do to halt or reverse climate change, he said: “There's the individual things we can do, like change the type of car that we drive, change to a plant-based diet or eat less meat, because we know those are carbon intensive.
“But in terms of broad global transformations that will require very specific efforts to reduce carbon emissions. We have to reduce carbon emissions, and that probably means a gradual or more rapid shift to a renewable economy.”
Alluding to the “flatten-the-curve” approach by countries battling to contain Covid-19, Dr Shepherd said the world also has to flatten the carbon dioxide emissions curve, and he believes that will happen through carbon mitigation strategies.
He said that in the short term there will need to be adaptation strategies, such as sea walls and retrofitting homes in very hot communities that may not have air conditioning.
“But the long term solution involves reducing fossil fuel emissions,” he said.