Global warming is the phenomenon of increasing average air temperatures near Earth's surface over
the past one to two centuries and is expected to increase by another degree at the end of the
century. Global warming’s main threat to coastlines is through rising sea levels which will therefore
create higher amounts of erosion and heavily impact communities which it has already been doing.
Although there are also other significant threats to coastlines and their communities such as….
The primary way that global warming affects sea levels is through thermal expansion and therefore
sea level rising. This occurs when water gets warmer, which causes the volume of the water to
increase, so therefore as a result of global warming. About half of the measured global sea level rise
on Earth is from warming waters and thermal expansion. This is a huge threat to communities as
global warming has already caused global sea level’s to rise by 24cm since 1880, with over 8 cm of
that since 1993 alone, this can dramatically increase the frequency and severity of coastal flooding,
especially during storms and high tides. Additionally, global warming also results in the melting of
glaciers due to rising temperatures and this has been significantly impactful in Greenland and
antarctica. For example, the Greenland Ice Sheet is currently losing around 270 billion tonnes of ice
per year, while Antarctica loses about 150 billion tonnes annually. Both of these consequences
which are brought about by global warming threaten a large amount of coastlines and their
communities. For example, in Bangladesh they are extremely vulnerable to sea level’s rising as
around 30% of Bangladesh’s population (over 50 million people) live in coastal areas. Additionally,
The IPCC predicts that sea levels could rise by up to 1 metre by 2100, which could submerge 17% of
Bangladesh’s land area and displace around 20 million people. Furthermore, Global warming has
intensified the frequency and strength of tropical cyclones in the Bay of Bengal and globally. For
example, Cyclone Sidr in 2007, killed over 3,000 people and caused $1.7 billion in damages, large
threats to both the coastline and their communities. All of these factors demonstrate the large
threat that global warming presents to coastlines and their communities, especially in vulnerable
areas such as Bangladesh
While global warming and rising sea levels are often cited as the greatest threats to coastal regions,
it can be argued that coastal erosion itself, driven by natural geological factors and local conditions,
poses an equally significant risk to coastlines and the communities that live along them. The rates of
coastal erosion are largely influenced by the lithology of the coastline, with sedimentary rocks such
as boulder clay being particularly vulnerable to rapid erosion whereas igneous and metamorphic
rock being more resistant . For instance, in areas like the Holderness Coast, where much of the
coastline is made up of unconsolidated materials and soft geology, erosion occurs at alarming rates
of 2-3 metres per year, and in some locations like Mapleton and Withernsea, it can exceed 4 metres
per year. This is considerably faster than the erosion rates in areas with harder igneous rocks, such
as granite in Cornwall, where erosion occurs at just 0.5-1 cm per year. Furthermore, the soft geology
along the Holderness Coast makes it one of Europe’s fastest eroding coastlines, and it is estimated
that over 10,000 people are affected by this rapid erosion, with 1,500 people at risk of losing their
homes, valued at over £300 million in potential damages (showing the threats it brings to the
communities and their people).Moreover, coastal erosion continues to be driven by natural
processes such as wave action and longshore drift, which can cause significant land loss over a short
period, irrespective of global warming. These factors therefore demonstrate that how coastal
erosion itself, driven by the vulnerable geology of a coastline can present a large threat to both
coastal communities and therefore people, in areas such as Holderness.
Finally another factor which can present a dangerous threat to coastlines and their communities is
human factors. On one hand human factor can actually decrease the risk to coastlines by
implementing shoreline managements plans in areas such as Holderness and attempting to slow