Golez: Just like Yolanda case: "It's a fact: climate change made Hurricane Harvey more deadly" | Michael E Mann https://t.co/5bKm1q4D1I
Last February 2014, as principal author of the Climate Change Act of 2009, I published a technical blog entitled: WARMING PACIFIC OCEAN, SEA LEVEL RISE, HAIYAN’S FURY AND SURGE – EXPECT MORE AND INCREASINGLY MORE INTENSE TYPHOONS IN THE COMING MONTHS AND YEARS BECAUSE OF CLIMATE CHANGE - Roilo Golez http://roilogolez.blogspot.com/…/warming-pacific-ocean-sea-…
The aforementioned technical blog raised points on why climate change aggravated Typhoon Haiyan or Yolanda in 2013, which points are very similar to this Guardian article about how climate change made Hurricane Harvey that hit Texas more deadly. I quote as follows:
1. Rising Sea Level that aggravated the surge (happened also in Yolanda case): "Sea level rise attributable to climate change – some of which is due to coastal subsidence caused by human disturbance such as oil drilling – is more than half a foot (15cm) over the past few decades (see here for a decent discussion). That means the storm surge was half a foot higher than it would have been just decades ago, meaning far more flooding and destruction."
2. Warmer sea surface temperature, also happened in Yolanda case: "In addition to that, sea surface temperatures in the region have risen about 0.5C (close to 1F) over the past few decades from roughly 30C (86F) to 30.5C (87F), which contributed to the very warm sea surface temperatures (30.5-31C, or 87-88F).
3. More water content in the atmosphere due to warm air, same as Yolanda: "There is a simple thermodynamic relationship known as the Clausius-Clapeyron equation that tells us there is a roughly 3% increase in average atmospheric moisture content for each 0.5C of warming. Sea surface temperatures in the area where Harvey intensified were 0.5-1C warmer than current-day average temperatures, which translates to 1-1.5C warmer than “average” temperatures a few decades ago. That means 3-5% more moisture in the atmosphere.
4. More water content in atmosphere, more rainfall, happened in Yolanda: "That large amount of moisture creates the potential for much greater rainfalls and greater flooding. The combination of coastal flooding and heavy rainfall is responsible for the devastating flooding that Houston is experiencing."
5. Warmer sea surface temperature in the Pacific Ocean made Yolanda more intense, same as Harvey case: "Not only are the surface waters of the Gulf of Mexico unusually warm right now, but there is a deep layer of warm water that Harvey was able to feed upon when it intensified at near record pace as it neared the coast. Human-caused warming is penetrating down into the ocean. It’s creating deeper layers of warm water in the Gulf and elsewhere."
"Sea surface temperatures in the region have risen about 0.5C (close to 1F) over the past few decades
"Harvey was almost certainly more intense than it would have been in the absence of human-caused warming, which means stronger winds, more wind damage and a larger storm surge. (As an example of how this works, we have shown that climate change has led to a dramatic increase in storm surge risk in New York City, making devastating events like Hurricane Sandy more likely.)"
"Finally, the more tenuous but potentially relevant climate factors: part of what has made Harvey such a devastating storm is the way it has stalled near the coast. It continues to pummel Houston and surrounding regions with a seemingly endless deluge, which will likely top out at nearly 4ft (1.22m) of rainfall over a days-long period before it is done.
"The stalling is due to very weak prevailing winds, which are failing to steer the storm off to sea, allowing it to spin around and wobble back and forth. This pattern, in turn, is associated with a greatly expanded subtropical high pressure system over much of the US at the moment, with the jet stream pushed well to the north. This pattern of subtropical expansion is predicted in model simulations of human-caused climate change.
"More tenuous, but possibly relevant still, is the fact that very persistent, nearly “stationary” summer weather patterns of this sort, where weather anomalies (both high-pressure dry hot regions and low-pressure stormy/rainy regions) stay locked in place for many days at a time, appears to be favoured by human-caused climate change. We recently published a paper in the academic journal Scientific Reports on this phenomenon.
Climate change worsened both Yolanda and Harvey:"In conclusion, while we cannot say climate change “caused” Hurricane Harvey (that is an ill-posed question), we can say is that it exacerbated several characteristics of the storm in a way that greatly increased the risk of damage and loss of life. Climate change worsened the impact of Hurricane Harvey."
Michael E Mann is distinguished professor of atmospheric science at Pennsylvania State University, director of the Penn State Earth System Science Center and author of three books, including The Hockey Stick and The Climate Wars, Dire Predictions, and The Madhouse Effect.