In the past month, our planet has experienced a turbulent assault of extreme weather events. This name is given to unusually severe weather or climate conditions that can cause impacts on communities and agricultural and natural ecosystems. Among these were June’s and July’s heat waves which struck the world with an unyielding force, setting hot-temperature records. These heat waves resulted in the hottest June ever recorded on Earth, and July being the hottest month ever recorded, (in 174 years of temperature records). Yes, ever. In the United States (US), the heat wave has been manifested in prolonged heat advisories, record-breaking temperatures in several cities (mainly in the South), and heat-related human and wildlife deaths. Additionally, other extreme-weather events have manifested as extreme rainfall, like those recorded in the states of Vermont and New York, where intense rainstorms produced flooding.
Boiling under the dome
Over a thousand high-temperature records have been broken across the US through June and July. An extreme case in the US is Saratoga Spring in Death Valley National Park, which reached 53.9 degrees Celsius (129°F), one of the hottest reliably measured temperatures recorded in history. The severity of this heat has been related to a phenomenon called a "heat dome," which is an immense area of high pressure that traps heat beneath it. This phenomenon has taken hold over the southern United States, and is just one of several heat domes present worldwide in the Northern Hemisphere. The intensity of this heat dome is unprecedented, exerting pressure from above and threatening to become the most severe on record over the southern United States. The consequences have been dire. In Southern Florida, the effects have been felt in in-land and offshore settings. Meanwhile, in-land temperatures have reached levels of 105-110°F (41-44°C), keeping nighttime lows excruciatingly high; the marine heatwave has produced an “above average” intensity when compared to previous historical marine heatwaves, posing a threat to corals and other types of marine lives.
Dr. Rosana Aguilera, a staff researcher in the groups of extreme weather events and climate change epidemiology at the Scripps Institution of Oceanography, explains that the effects of these extreme phenomena have been reinforced by the beginning of El Niño Southern Oscillation, which causes above-average sea-surface temperatures across the east-central equatorial Pacific, producing higher temperatures worldwide. Overall, climate scientists agree with this relationship. As the WMO Secretary-General Prof. Petteri Taalas said, “The onset of El Niño will greatly increase the likelihood of breaking temperature records and triggering more extreme heat in many parts of the world and in the ocean.”
A Tale of Fire and Rain
The prolonged heat wave has left communities grappling with the harsh reality of climate change. The high temperatures have made a considerably high number of United States residents—over 100 million— find themselves under heat advisories in the past weeks, which signals the scale of the reach of these events. The population from cities such as Las Vegas and Phoenix have been under weather advisories for several days, with warnings from local weather forecasters of not going outdoors between 9 am and 6 pm.
As Aguilera pointed out, the effects of heat waves (such as dehydration, heat-related strokes, sickness, etc.) may not equally affect populations in the same way, given pre-existent conditions and socio-economic vulnerabilities. So far, heat-related deaths have been reported across multiple states, highlighting the vulnerability of those without adequate protection from the scorching elements.
While the heat wave blazed relentlessly in the south of the US, another extreme-weather vent struck the Northeastern United States in early July. Dr. Jason Cordeira, the Atmospheric Science and Applications Manager at the Center for Western Weather and Water Extremes at the Scripps Institution of Oceanography, says that a series of various events occurring at different scales unchained the flooding, including 1) extremely high rainfall rates (about two months' worth of rain fell in two days), 2) persistent warm and humid airmass with tropical moisture, 3) A series of "forcing mechanisms" that convert the tropical moisture into rainfall, and 4) ground saturation conditions produced by widespread thunderstorms and showers, among others.
Combined with other geological and geographical conditions, these ingredients were the perfect mix that led to prolific flooding in portions of New York's Hudson Valley and Vermont. The flooding led to evacuations, fully or partially destroyed homes and businesses, and tragically, one flood-related death was reported in Vermont after this event. The event concluded with a Federal declaration of a state of emergency, unlocking federal resources to aid the state's recovery.
Although it is hard to attribute any single event to climate change, Dr. Cordeira remarked, "Science has shown that the frequency of extreme rainfall events is increasing over the Northeast U.S. and New England in tandem with warming driven by climate change. Warmer air simply holds more water vapor which can, in turn, produce more rainfall.”
The severe effects of the extreme weather events in the past month are leaving a lasting impact on our planet and its inhabitants. Global authorities, such as UN Secretary Antonio Guterres, manifested that “the era of global warming has ended, the era of global boiling has arrived,” referring to the recent global temperature records. The consequences of the past months’ extreme weather events, such as the flooding in the Northeast, remind us that no region is immune to the effects of climate-related events. Earth is giving humanity wake-up calls, but as scientists and climate authorities indicate, the severity of the events is becoming high to prepare humanity for the consequences of not answering those calls.