By Julia Evans, JOHANNESBURG South Africa
A Russian Su-27 jet fighter
collided with an American MQ-9 Reaper drone over the Black Sea on Tuesday, the
US military's European Command said. Locals are evacuated from flooded areas in Maputo, Mozambique
Tropical Cyclone Freddy has
become the longest-lived tropical cyclone on record and the first tropical
cyclone to hit both Mozambique and Madagascar twice.
“Initially, 14 people lost
their lives in Madagascar and Mozambique. But after the second landfall, the
loss of life was much greater,” SA Weather Service (SAWS) forecaster Wayne
Venter told our reporter, with the death toll on Tuesday surpassing 200.
In an unprecedented turn of
events, after making landfall in Madagascar on 21 February and Mozambique on 24
February, instead of continuing westwards as tropical cyclones typically do,
Freddy returned to the Mozambique Channel, gathering energy from the ocean, and
hitting Madagascar again before heading back to Mozambique.
Freddy made its second
landfall in Mozambique on 11 March, displacing 22,000 people (with 10 confirmed
deaths by Tuesday) and then moved inland towards southern Malawi.
As the death toll in Malawi
neared 100, President Lazarus Chakwera declared
a State of Disaster in the southern region of the country on Monday.
On Tuesday afternoon,
the Department of Disaster Management Affairs in Malawi reported the death
toll had risen from 99 to 190, with 584 injured and 37 reported missing.
Francois
Engelbrecht, a professor of climatology and the director of the Global
Change Institute at Wits University, said Freddy is the longest-lived
tropical cyclone on record. The period from when it first attained tropical
cyclone status to the last day that it had tropical cyclone status was 35 days,
although at times it weakened into a tropical low.
SAWS forecaster Venter said
the previous record was held by Hurricane John in 1994 — 31 days — but
meteorologists were still awaiting confirmation of Freddy’s record from the
World Meteorological Organization.
Along with climate change
making cyclones more intense — read
this if you’re not convinced — Engelbrecht said that in a warmer
world, it’s logical that tropical cyclones will last longer too.
He explained that tropical
cyclones need warm tropical water, with sea surface temperatures higher than
27°C to maintain their intensity. When a system is over colder water, or if it
encounters unfavourable circulation in the atmosphere, it can lose its tropical
cyclone status.
“It is actually very logical
that in a warmer world, where the tropical oceans are also getting warmer and
where regions such as the Mozambique Channel are also getting warmer, we should
expect that conditions are becoming generally more favourable to maintain
tropical cyclones,” said Engelbrecht.
Along with lots of heat being
exchanged between the ocean and the atmosphere, evaporation also occurs.
“The warmer the sea surface
temperature is, the more evaporation takes place from the ocean into the
atmosphere,” said Engelbrecht, explaining that rising air in a tropical cyclone
leads to the condensation of water vapour.
That latent heat from the
water vapour is released into the storm when the water vapour condensates to
form clouds, providing additional energy.
“This disaster is
unprecedented,” said John Chipeta, senior advocacy, communications and
campaigns manager for the international development and humanitarian aid
organisation Save the
Children in Malawi.
Chipeta said the cyclone
hadn’t just affected the hotspot areas for annual flooding, particularly
low-lying areas, but had “affected even Blantyre city in the southern part of
Malawi; normally [that area] doesn’t experience that level of destruction and
disaster”.
On Monday, 13 March, the
Malawian government reported that Blantyre city and district had more than
1,600 people displaced, 98 dead and 134 missing.
Chipeta said they had to
evacuate people from mudslides where houses had been built in mountainous
areas.
Engelbrecht said that some of
the houses in Blantyre are built from mud, which caused the houses to collapse
when hit with extreme rainfall — similar to what occurred with the fatal KwaZuluNatal
mudslides last year.
“It’s a new phenomenon in this
disaster,” said Chipeta. “We haven’t had this in a long time.”
Engelbrecht said that Freddy
developed a “sequence that has never been before”.
He said that the cyclone
making landfall in Madagascar, moving to the Mozambique Channel, and making
landfall in Mozambique was not uncommon, but what was strange was that the
cyclone moved back into the Mozambique Channel — usually, cyclones in the area
keep going westwards and peter out.
Scientists are not sure why
this happened, but Engelbrecht says Freddy was a very slow-moving cyclone and
never completely lost touch with the ocean.
“So, over the warm waters it
started to regenerate itself,” said Engelbrecht.
“Once again, the climate
system has surprised us. The question we, as climatologists, need to pose is
whether these higher sea surface temperatures in the southwest Indian Ocean,
including in the Mozambique Channel, are now enabling generally longer lifetime
for tropical cyclones.”
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