Faced with exploding populations and steadily rising temperatures worldwide, cities must make haste in reinforcing defenses against climate change-induced flooding and heat waves, experts said last week.
City temperatures are forecast to shoot up in the coming years, exposing inhabitants to killer heat spikes, while rising sea levels and river flooding threaten homes, drinking water, and transport and electricity infrastructure.
Cities are vulnerable to a unique risk called the “urban heat island” (UHI) effect — their concrete surfaces retain more of the sun’s heat than undeveloped areas, scientists said at a meeting in Vienna of the European Geosciences Union (EGU).
Photo: Bloomberg
By midcentury, if planet-warming fossil fuel emissions continue unabated, city temperatures in Belgium could exceed today’s heat-alert levels by as much as 10?C for 25 days each summer, according to one research paper.
Another study showed that heat waves will become a frequent challenge for European cities — more numerous in the south of the continent, more intense in the north.
Floods, a major risk to Europe’s dense urban settlements, will become more common because of an increase in freak rainstorms, as well as sea-level increases caused by polar ice melt and warmer ocean water expanding.
In flood-prone Southeast Asia, precipitation is set to increase by 20 percent this century, one researcher said in Vienna.
The stakes are especially high given the projections for expansion of urban areas, which are often ill equipped to deal with nature’s vengeance.
Already, more than half the world’s population live in cities. By 2050, 80 percent of people in rich nations, and 60 percent in developing states, will be concentrated in built-up areas, according to recent calculations.
This corresponds to the appearance of a settlement of 1 million inhabitants somewhere on the globe every week for the next 40 years.
Occupying only a small portion of Earth’s available land, cities are responsible for 80 percent of all energy consumed and generate more than 60 percent of the planet-warming greenhouse gases emitted when humans burn fossil fuel for heating, power and transportation.
In spite of efforts to curb emissions, the planet has already warmed about 1?C on average from pre-Industrial Revolution levels.
Many scientists say the planet may be on track for 3?C of warming or more, exceeding the 2?C cap politicians set in Paris in 2015.
This means cities must act now to shore up their defenses against impacts that can no longer be avoided, French climatologist Herve le Treut said at the annual EGU gathering.
“It’s already happening,” Le Treut said of climate change impacts. “We have to start structural action quickly: transportation, houses... mainly in the cities, especially in vulnerable places.”
Most of the infrastructure constructed by humanity is in urban zones.
“The ways cities are built is not optimal” for today’s climate reality, said Daniel Schertzer, a hydrometeorologist at the engineering school Ecole des Ponts ParisTech.
“Historically, humans have settled near water, thinking of its usefulness, but not of the risk! Cities were conceived without taking geophysics into consideration, now they are discovering that nature is complicated, not just good,” he said on the sidelines of the conference.
Paris, for example, is due for its next so-called one-in-a hundred-year flood. The last major Paris flood, in 1910, saw the Seine river rise 8.62m, shutting down much of the City of Light’s basic infrastructure.
“It ... will occur some day,” said Sebastien Maire, who goes by the title of Paris’s chief resilience officer.
When it does, research shows it will cost about 100 billion euros (US$109 billion) and about 400,000 jobs, and harm France’s economic output for five years afterwards.
Paris is vulnerable because much of its critical infrastructure lies near the Seine — including power distribution, heating, telecommunications and fresh water networks.
Maire is part of 100 Resilient Cities, a think tank created to help city planners prepare for natural shocks such as hurricanes, earthquakes, fires and floods.
One solution mooted at the conference was “greening” cities via balcony and rooftop gardens to counter the effects of “urban heat islands” — since plants absorb heat.
Another proposed using uchimizu, a technique used in 17th-century Japan to gather rainwater and sprinkle it on the ground to reduce surface-level temperatures.
Thousands gathered across New Zealand yesterday to celebrate the signing of the country’s founding document and some called for an end to government policies that critics say erode the rights promised to the indigenous Maori population. As the sun rose on the dawn service at Waitangi where the Treaty of Waitangi was first signed between the British Crown and Maori chiefs in 1840, some community leaders called on the government to honor promises made 185 years ago. The call was repeated at peaceful rallies that drew several hundred people later in the day. “This government is attacking tangata whenua [indigenous people] on all
A colossal explosion in the sky, unleashing energy hundreds of times greater than the Hiroshima bomb. A blinding flash nearly as bright as the sun. Shockwaves powerful enough to flatten everything for miles. It might sound apocalyptic, but a newly detected asteroid nearly the size of a football field now has a greater than 1 percent chance of colliding with Earth in about eight years. Such an impact has the potential for city-level devastation, depending on where it strikes. Scientists are not panicking yet, but they are watching closely. “At this point, it’s: ‘Let’s pay a lot of attention, let’s
UNDAUNTED: Panama would not renew an agreement to participate in Beijing’s Belt and Road project, its president said, proposing technical-level talks with the US US Secretary of State Marco Rubio on Sunday threatened action against Panama without immediate changes to reduce Chinese influence on the canal, but the country’s leader insisted he was not afraid of a US invasion and offered talks. On his first trip overseas as the top US diplomat, Rubio took a guided tour of the canal, accompanied by its Panamanian administrator as a South Korean-affiliated oil tanker and Marshall Islands-flagged cargo ship passed through the vital link between the Atlantic and Pacific oceans. However, Rubio was said to have had a firmer message in private, telling Panama that US President Donald Trump
The administration of US President Donald Trump has appointed to serve as the top public diplomacy official a former speech writer for Trump with a history of doubts over US foreign policy toward Taiwan and inflammatory comments on women and minorities, at one point saying that "competent white men must be in charge." Darren Beattie has been named the acting undersecretary for public diplomacy and public affairs, a senior US Department of State official said, a role that determines the tone of the US' public messaging in the world. Beattie requires US Senate confirmation to serve on a permanent basis. "Thanks to