Memories are still fresh when the highest ever temperature was recorded in the Arctic in 2020, severe flooding in Germany and Belgium in July 2021, hurricanes caused havoc in the U.S. near the end of last year, and much more catastrophic events happened in recent decades. It can be seen that hazardous weather events occur more adversely on a larger scale. With that being said, each of us cannot eliminate the risk of being influenced by extreme weather conditions.
Definition and cause of extreme weather conditions
According to the Climate Hubs of U.S. Department of Agriculture, extreme weather conditions are occurrences of unusually severe weather or climate conditions that can cause devastating impacts on communities and agricultural and natural ecosystems (1). Extreme weather conditions happen occasionally, but what has made them more frequent and severe in recent years? Carbon Brief, a U.K.-based non-profit organization, conducted research on the correlation between extreme weather conditions and global warming. They reviewed more than 400 extreme weather events which mainly happened on or after 2011. Results showed that 70% of these events were more likely to occur or were made more severe, because of human-caused global warming (2). The answer is yet to be confirmed, but more and more evidence has shown that human activities alter the atmospheric environment.
Similar findings are concluded by the Intergovernmental Panel on Climate Change (IPCC) (3). They also discovered that human influence is likely to be the main driver of climate change. Specifically, the likely range of total human-caused global surface temperature increase from 1850-1900 to 2010-2019 is 0.8 to 1.3°C. The following figure illustrates the changes in global surface temperature relative to 1850-1900. It shows that human factors highly affected the temperature change within 1850-2020.
The report stated that every additional increment of global warming results contributes to a surge in extreme weather conditions. A case in point is every additional 0.5°C of global temperature increase leads to more heatwaves, heavy precipitation and on the contrary, droughts. From Figure c) below, simulations demonstrate the changes in terms of precipitation given temperature changes. A higher global surface temperature brings a more extreme climate condition that it would be drier near the center of the Atlantic Ocean and the Southern Hemisphere, while it would be wetter near the equator, South and North Pole.
Case study 1: Unprecedented snowstorm in Spain
Date: Early-mid January 2021
Location: Mainly in central, northern, and eastern Spain (4)
Cause: Snowstorm originated over the mid-Atlantic, caught up with the shallow low-pressure center southwest of Spain. The exceptional cold air advection gives rise to the heavy snowfall (5).
How: An all-time record of ~40-50 centimeters of snow fell in Madrid, where the authorities in the territory activated a ‘red alert’ for the first time since the system was adopted four decades ago (6). Two Spanish cities, Toledo and Teruel, recorded the lowest ever temperature (-13.4°C and -21.0°C respectively) on 12 January (7).
NASA Earth Observatory declared that nearly 700 streets and highways were impassable by the snowstorm. At least four people died and thousands of travellers were left stranded. All flights were cancelled on 8 January at Madrid’s international airport.
Case study 2: One-in-a-thousand year heatwave in North America
Date: June & July 2021
Location: North America, mainly in the western areas of Canada and the US
Cause: According to the Washington Post, the skyrocketing temperatures can be traced to a sprawling ridge of a “heat dome” (8). When hot air masses expand vertically into the atmosphere, a dome of high pressure is formed (See figure below). High pressure pushes warm air down toward the ground, causing a surge in temperature (9). The maximum temperature was also considered virtually impossible without human-caused climate change, that this event has been at least 150 times rarer (10).
How: World Meteorological Organization found that the north-western United States and western Canada suffered the most from the heatwave. Record-breaking peak temperatures are recorded in numerous places. Lytton, a village located in south-central British Columbia, reached 49.6°C on 29 June, which broke the previous Canadian national record by 4.6°C.
The heatwave caused wildfires in the affected area. A wildfire named ‘Dixie fire’ starting from 13 July till 7 October had burned about 390,000 hectares, which is the largest single fire on record in California.
How people can help alleviate extreme weather conditions
Extreme weather conditions bring everyone’s attention to climate emergency, and the fate of planet earth and human beings are up in the air. It is inevitable that the number of devastating weather conditions will rise, which will put our lives in peril. Therefore, we have to prepare for the worst scenario in case of any casualties and fatalities. Not only do all infrastructure have to be improved, but the government should also devise a comprehensive plan to evacuate citizens when extreme weather strikes the territory. To start off a new year, we hope the incoming extreme weather conditions will be less devastating.
References:
USDA Climate Hubs. (n.d.). Extreme Weather. Retrieved December 20, 2021, from https://www.climatehubs.usda.gov/content/extreme-weather
Sullivan, B. K., & Roston, E. (2021, December 1). How Science Links Global Warming to Extreme Weather. Bloomberg.com. Retrieved December 21, 2021, from https://www.bloomberg.com/news/articles/2021-12-01/how-science-links-global-warming-to-extreme-weather-quicktake
IPCC, 2021: Summary for Policymakers. In: Climate Change 2021: The Physical Science Basis. Contribution of Working Group I to the Sixth Assessment Report of the Intergovernmental Panel on Climate Change [Masson- Delmotte, V., P. Zhai, A. Pirani, S.L. Connors, C. Péan, S. Berger, N. Caud, Y. Chen, L. Goldfarb, M.I. Gomis, M. Huang, K. Leitzell, E. Lonnoy, J.B.R. Matthews, T.K. Maycock, T. Waterfield, O. Yelekçi, R. Yu, and B. Zhou (eds.)]. Cambridge University Press. In Press.
NASA. (n.d.). Heavy snowfall blankets Spain. NASA Earth Observatory. Retrieved December 22, 2021, from https://earthobservatory.nasa.gov/images/147768/heavy-snowfall-blankets-spain
Mahovic, N. S., Kerkmann, J. K., Prieto, J., Smiljanic, I., & Kocsis, Z. (2021, January 12). Heavy snow in parts of Spain. Retrieved December 23, 2021, from https://www.eumetsat.int/heavy-snow-in-spain
Euronews. (2021, January 9). In pictures: Spain under Snow as weather alerts remain in place. Retrieved December 22, 2021, from https://www.euronews.com/2021/01/09/in-pictures-swathes-of-spain-under-drifts-of-snow-as-weather-alerts-remain-in-place
World Meteorological Organization. (n.d.). State of the Global Climate 2021 WMO Provisional report. Retrieved December 23, 2021, from https://library.wmo.int/doc_num.php?explnum_id=10859
Cappucci, M., & Samenow, J. (2021, June 25). Weather Service warns of 'dangerous' and 'historic' heat wave in Pacific Northwest. The Washington Post. Retrieved December 26, 2021, from https://www.washingtonpost.com/weather/2021/06/22/heat-wave-pacific-northwest-historic/
Samenow, J., Moriarty, D., Karklis, L., Leonard, D., & Galocha, A. (2021, June 18). How a heat dome is pushing extreme temperatures to new heights in the West. The Washington Post. Retrieved December 26, 2021, from https://www.washingtonpost.com/weather/2021/06/18/heat-dome-western-us-temperatures/?itid=lk_interstitial_manual_20
Philip et al. (n.d.). Rapid attribution analysis of the extraordinary heatwave on the Pacific Coast of the US and Canada June 2021. World Weather Attribution. Retrieved December 24, 2021, from https://www.worldweatherattribution.org/wp-content/uploads/NW-US-extreme-heat-2021-scientific-report-WWA.pdf