When you buy through link on our website , we may earn an affiliate committee . Here ’s how it works .
The historical Egyptian city of Alexandria is crumble due to rising sea levels , scientists have found .
Over the past decade , the rate at which buildings have collapsed along the ancient metropolis ’s seafront has increased from around one per year to as many as 40 per year , concord to a field publish Feb. 12 in the journalEarth ’s Future .
Buildings in the ancient coastal city of Alexandria are collapsing at an ever increasing rate as a result of sea level rise.
In the past 20 years , 280 buildings in this 2,300 - class - erstwhile porthole city — known for being the place of birth of Cleopatra and the ancient home of the famed Library of Alexandria — have collapsed due to coastal erosion , and 7,000 more are at jeopardy of collapsing in the future , according to the paper . Between 2014 and 2020 alone , 86 construction totally collapse , and 201 partially give way across the urban center , ensue in 85 death .
" The true cost of this going extends far beyond brick and mortar , " study co - authorEssam Heggy , a water scientist at the University of Southern California ’s Viterbi School of Engineering , said in a statement . " We are witnessing the gradual disappearance of historical coastal cities , with Alexandria vocalise the dismay . What once seemed like distant clime risks are now a present world . "
The crumbling of coastal building results from sea level rise and the subsequent intrusion of seawater into the flat coat under the city . As saltwater creeps far inland due to rising sea degree , it increases groundwater level beneath buildings and other infrastructure and gnaw at the grunge . This can go the ground to lapse , which make building unstable and at peril of collapse . Additionally , brine corrodes the steel reinforcement of build foundations , further weakening the structures .
Alexandria is a port city that sits on the coast of the Mediterranean Sea, making it vulnerable to seawater intrusion.
Average globular sea levels have risen by between 8 and 9 inch ( 20 to 23 cm ) since 1880 , with a 4 - inch ( 10 centimetre ) rising slope since 1993 alone , according to theNational Oceanic and Atmospheric Administration(NOAA ) . If nothing is done to curb clime change , U.S. ocean levels could rise by as much as 7.2 feet ( 2.2 metre ) by 2100 equate with the level seen in 2000 .
Low - lying cites confront the high risk of erosion and flooding due to sea level rise , especially those along the U.S. East Coast , West Coastand Gulf Coast , allot to NASA .
" Our study challenges the usual misconception that we ’ll only postulate to vex when sea levels rise by a measure , " Heggy said . " However , what we ’re showing here is that coastlines globally , especially Mediterranean coastlines similar to California ’s , are already change and causing building crash at an unprecedented charge per unit . "
Alexandria’s coastline has undergone significant changes, with the western and eastern shores retreating dramatically between 1935 and 2022.
In the study , the researcher mapped collapsed buildings around Alexandria between 2001 and 2021 , and compared artificial satellite images from between 1974 and 2021 with maps of the city from 1887 , 1959 and 2001 to determine ocean stage ascent . Using this information , they limit that Alexandria has seen its coastline move inland by tens of meters over the past few decennary , with some region feel up to 79 to 118 feet ( 24 to 36 m ) of soil erosion per year .
The researcher also analyzed chemical substance isotopes in the stain to determine the degree of ground wearing .
" Our isotope depth psychology uncover that buildings are collapse from the bottom up , as seawater trespass erode foundations and weakens the soil , " study Colorado - authorIbrahim Saleh , a soil radiation scientist at Alexandria University , say in the program line . " It is n’t the construction themselves , but the ground underneath them that ’s being affected . "
In the historic coastal districts of Alexandria, buildings are sinking as rising groundwater seeps up from below.
— percentage of San Francisco and Los Angeles are subside into the sea — mean sea - level rise will be even spoilt
— Ancient seafloor spreading 15 million years ago caused sea levels to plump
— Scientists identify tipping point for Greenland ’s shabu sheet — and it ’s not far off
The researchers indicate several ways that Alexandria could organise for the oncoming barrage of seawater . These steps include building sand sand dune and other barriers along the coast , kick upstairs construction , and relocating people who live in the high - risk areas .
" historical cities like Alexandria , which represent the provenience of cultural exchange , innovation and history , are all important for safeguard our portion out human inheritance , " Heggy said . " As climate change accelerates sea level wage hike and coastal wearing away , protecting them is n’t just about saving buildings ; it ’s about save who we are . "
You must confirm your public display name before commenting
Please logout and then login again , you will then be move to enter your presentation name .
