Scientists believe that we will breach the 1.5°C within a few years. Researchers point to a 66% chance that we will overshoot the temperature threshold between now and 2027.
Breaching 1.5°C, even for a year, will mean global warming is accelerating and not declining. The world will have to expect longer heatwaves, record-breaking temperatures, severe droughts, stronger storms, and wildfires.
Scientists use average temperature data from pre-industrial times between 1850-1900, before our modernisation’s heavy reliance on coal, oil and gas.
For decades scientists placed the temperature thresholds at 1.5°C or well below 2°C, believing there would be severe climate change consequences for the planet if the temperature rose to this level. Scientists have warned that crossing the 1.5°C threshold risks unleashing more severe climate change effects on people, wildlife, and ecosystems.
However, temperatures have climbed steadily every decade since the pre-industrial period, making 2016 the warmest year on record, with global temperatures reaching 1.28°C.
In the last three years, from 2020 to 2022, the planet was under La Niña, a cooler phase of the El Niño Southern Oscillation (ENSO), a naturally occurring climate pattern.
ENSO normally transitioned from La Niña to El Niño every two to five years. However, in 2022, the waters cooled in the Pacific for a third consecutive year, bringing a rare “triple-dip” La Nina and lessening the planet’s warming to some extent.
This year, 2023, we have the El Niño phase, which will bring extra heat to the surface of the Pacific and will likely push temperatures to new records. According to WMO, simultaneous heat waves are sweeping across much of the Northern Hemisphere.
Heatwaves are ripping through Europe, Asia and the United States. USA Today reports that record-breaking temperatures and hitting multiple cities. Phoenix recorded an unprecedented nineteen consecutive days over 43°C (110 F) on 18 July, breaking its record of 18 days. Death Valley reached 53.33°C (128 F) on 16 July, as temperature records are being broken everywhere. According to the news, the extreme temperatures recorded this summer result from natural variations in the climate system, climate change, and El Niño.
Heat domes and anticyclones or high-pressure systems are blamed for heat waves in several parts of the world this year. Although they do not occur because of climate change, scientists believe they have become more intense and prolonged because of increasing global temperatures.
According to The Conversation, a heat dome occurs when a persistent region of high-pressure traps heat over an area. A heat dome can stretch over several states and linger for days to weeks leaving stagnant hot air that can feel like an oven.
Heat domes are also linked to the behaviour of the jet stream, a band of fast winds high in the atmosphere that blows from west to east.
Studies suggest that the jet stream has become wobblier as the planet warms. And bends in the jet stream have strapped hot air in domes over parts of the US and Europe, fueling severe heat and intense wildfires.
In Europe, heatwaves are fuelling wildfires in Greece as the World Meteorological Organization (WMO) warns that heatwaves in the northern hemisphere are set to intensify. The country has been grappling with searing heat, with temperatures surpassing 40°C. What started as 64 wildfires on 23 July has grown to 82 the following day across Greece.
The most serious of the fires is on the island of Rhode with some 19,000 people, including tourists, evacuated. Greece’s Ministry of Climate Change and Civil Protection labelled the event “the largest evacuation from a wildfire in the country.”
Heatwave, a silent killer
When it gets too hot, the heart pumps blood much faster around the body and can lead to organ failure. As the body struggles to cool down, stress can also overwhelm the body. Internal body temperature can rise from the normal 37°C to a fatal 40°C. People working outside and experiencing direct heat can die immediately of heatstroke.
Europe has warmed nearly twice the global average, creating less extreme cold and more extreme heat.
According to The Guardian, if the planet surpasses the 2°C warming threshold, it will increase the intensity and the frequency of heat waves. Heatwave events will rise threefold in northern Europe and sixfold in southern Europe. A scorching heatwave that comes once in 100 years will come every five years in Northern Europe and every other year in South Europe.
As heatwaves become more frequent, it will also be detrimental to food and crop production. The European heatwave of 2018 led to multiple crop failures and 50% yield loss in central and northern Europe. In 2022, record temperatures in the UK killed its fruit and vegetables (Weston, 2023).
Climate change also does not just increase atmospheric heatwaves but ocean temperatures. Marine heatwaves can kill coral reefs affecting coastal communities, particularly in poor countries that rely on them for food and livelihood.
Growing GHG emissions is heating the planet. Global leaders need to act fast to meet the Paris Agreement they signed in 2015 to limit heating to 1.5°C by the end of the century.
Stallard, E. & Rowlatt, J. (2023, 21 July). World will miss 1.5C warming limit – top UK expert. BBC. Retrieved from https://www.bbc.com/news/science-environment-66256101
Weise, E. (2023, 19 July). Summers are always hot. Here’s how we know climate change is making summer 2023 hotter. USA Today. Retrieved from https://www.usatoday.com/story/news/nation/2023/07/19/is-climate-change-to-blame-for-summer-2023s-record-heat-yes/70424640007/
Gallus, W. (2022, 23 June). What is a heat dome? An atmospheric scientist explains the weather phenomenon baking Texas and the Southwest. The Conversation. Retrieved from https://theconversation.com/what-is-a-heat-dome-an-atmospheric-scientist-explains-the-weather-phenomenon-baking-texas-and-the-southwest-185569
Weston, P. (2023, July 21). Rampant heatwaves threaten food security of entire planet, scientists warn. The Guardian. Retrieved from https://www.theguardian.com/environment/2023/jul/21/rampant-heatwaves-threaten-food-security-of-entire-planet-scientists-warn
19,000 people have been evacuated as a wildfire rages on the Greek island of Rhodes. (2023, 23 July). NPR. Retrieved from https://www.npr.org/2023/07/23/1189655610/2-000-people-have-been-evacuated-as-a-wildfire-rages-on-the-greek-island-of-rhod
Smith, H. & Chisafis, A. (2023, July 23). Greece carries out its biggest ever evacuation as wildfires rage on Rhodes. The Guardian. Retrieved from https://www.theguardian.com/world/2023/jul/23/high-winds-expected-to-impede-fight-wildfires-in-rhodes