Vietnam Climate Change
Southeast Asian nation of Vietnam is highly exposed to climatic dangers, harsh weather, and climatic
disasters. Without additional actions, climate change is expected to result in higher temperatures, more
frequent and severe extreme weather events, and rising sea levels. These factors will increase the
population at risk of developing diseases that are sensitive to the climate.
1,2 The health effects of climate change can be direct and immediate, such as drownings, injuries, and
heat-related illnesses, or indirect and delayed, such as waterborne infections, vector-borne diseases, airborne diseases, mental health consequences, and food shortages.
3-7 Increases in the number of cases of climate-sensitive diseases can increase pressures on health care
system, especially in low- and middle-income countries. WHO8 projected the potential risks of climate
change for priority climate-sensitive health risks in 2030 and 2050 under different climate and
development scenarios. Under a base case socioeconomic scenario, climate change was estimated to
cause approximately 250 000 additional deaths per year worldwide from heat stress, diarrhea, malaria,
and undernutrition in 2030 and to put 4.26 billion people at risk of dengue in 2030, 4.64 billion people at
risk in 2050, and an additional 48 000 deaths in 2030 and 33 000 deaths in 2050 among children below
15 years due to diarrheal diseases.8 Natural disasters such as storms and floods can damage
infrastructure and disrupt the capacity of health systems to respond to health crises and affect the
overall quality of and access to health care.
6,9,10 Climate change will be a major challenge to the capacity of the Vietnamese health system in the
coming decades.The Global Climate Risk Index 2020 ranked Vietnam as the sixth country in the world
most affected by climate variability and extreme weather events over the period 1999-2018.
11 Climate change is projected to increase the frequency of natural disasters and extreme heat events in
most areas in Vietnam. Inundation due to sea-level rise of 100 cm could affect about 16.8% of the
population of the Red River Delta, 1.5% of the Central coastal provinces, 17.8% of Ho Chi Minh City, and
38.9% of the Mekong Delta.12 Extreme temperature and the number of hot days and nights were
projected to have an upward trend, and droughts could become more severe due to rising temperatures
and decreasing rainfall.
12 Several small-scale studies explored the relationship between weather variables, climate change, and
diseases such as diarrhea, dengue fever, malaria, and respiratory diseases in some provinces and cities
in Vietnam.
13-15 However, to our knowledge, no publication has comprehensively assessed health risks from
climate change in the country.The adaptive capacity of the health sector is an important determinant of
community vulnerability to climate change. Especially in rural areas, the health system faces increasing
challenges from changing climatic conditions and extreme weather events.
16 Commune health stations, for example, often did not have enough equipment and medicine for first
aid or treatment (especially waterborne disease outbreaks) during and after heavy rainfall and floods.
17 Isolated facilities could be severely damaged in some extreme weather events.
Introduction
Global climate change is one of the greatest environmental threats facing the world. Human activities
such as the burning of fossil fuels and deforestation over the past 150 years have led to the emissions of
massive amounts of greenhouse gases (eg carbon dioxide and methane). These gases are increasing the
amount of heat trapped in the atmosphere leading to changes in climate faster than at any time since
the transition from the last ice age 10,000 years ago [1]. The consequences will be grave: large rises in
sea level causing widespread coastal flooding; more severe weather (droughts in some areas, storms in
others); and major threats to agriculture and natural ecosystems. Those affected most will be those
already vulnerable today: people in poorer countries and endangered wildlife.
The choices that society makes on the use of engineering today and in the near future will be
instrumental in determining whether we successfully tackle the problem or not. In this paper I briefly
outline some of the main technical options for dealing with climate change, and highlight the ethical
dilemmas that surround these options.
Reducing Greenhouse Gases
Because so many human activities result in emissions of greenhouse gases (GHGs), there is a very wide
range of possible ways of reducing these emissions. Here I focus on three areas of particular importance
to engineering:
Changes in energy production
Improvements in energy-efficiency by technical means
Reducing GHG emissions by social means
Changes in energy production
Energy production can be changed in several ways to reduce emissions. For a start we can switch away
from coal and oil to gas, as gas emits only half the CO2 of coal and two-thirds the CO2 of oil per Joule of
energy used. A further way is to expand the use of Combined Heat and Power (CHP or cogeneration)
plants. Such plants use the waste heat from electricity production to provide space heating or hot water
for local buildings. Whereas conventional plants producing electricity work at efficiencies of about 35%
to 45%, CHP plants work at efficiencies of up to 85%.
Of course, the most effective change in the production of energy would be to use energy sources which
do not emit any GHGs at all during operation. Renewable energy sources, such as solar, wind, hydro,
biomass and geothermal, obviously fit into this category. Of these, wind energy (both on-shore and offshore) has the highest potential in the UK. Onshore wind can already produce electricity at a
competitive price, while the price of offshore wind is falling fast. The UK Government has set a target of
20% of electricity generation to be from renewable energy sources by 2020. Studies shows that the
potential is much higher than this [2].
One problem, however, with some renewable energy sources is that they are intermittent: the sun does
not shine all the time, and the wind does not blow all the time. Hence an important consideration is the
required level of 'back-up' power plants (which can be other renewable sources, eg biomass, or not) to
prevent power shortages. Power storage is also a way of dealing with the intermittency problem however, this is still at an early stage of development. A growing number of energy producers envisage
an eventual switch to the 'hydrogen economy'. This would be where energy sources (mainly renewable)
are used to produce hydrogen from water by electrolysis, which is then stored or transported as
required, to be used to deliver electricity from the recombination of the hydrogen and oxygen in a fuel
cell. This technology is still at an early stage of development.
Nuclear power is another energy source which produces no GHG emissions during operation (although
emissions from uranium mining and plant construction are not negligible). Currently nuclear power
supplies 22% of the UK's electricity and 16% of world electricity [3]. It has the advantage over wind and
solar energy in that it is not an intermittent supply, but of course it is highly controversial as I shall
discuss later.
A further option for dealing with the CO2 emissions of energy plants is CO2 capture and storage. This is
where CO2 is removed from the exhaust gases of a fossil fuel plant and piped into underground
geological formations, eg former oil reservoirs. Again, the controversies surrounding this technology will
be discussed later.
Improvements in energy-efficiency by technical means
The potential for technical change to lead to energy efficiency improvements as a way of reducing GHG
emissions is very high. For example, most buildings in the UK are not well insulated due to (up until
recently) low energy efficiency standards being followed in the building industry. Since most buildings
are heated using fossil fuels, either directly or indirectly, a large amount of GHG emissions are
needlessly produced. Large-scale deployment of building insulation will thus yield significant savings.
Further, the recent improvements in the energy efficiency standards governing household appliances is
beginning to have an effect.
One of the largest sources of GHG emissions in the UK is from motor vehicles. The recent introduction of
the first 'hybrid' cars, which use a combined petrol-driven motor with an electric motor, can reduce fuel
consumption by up to 50%. The promise of using fuel cells (see above) to drive motor vehicles has the
potential to reduce GHG emissions further.
Reducing GHG emissions by social means
It is also important to consider social changes which could reduce GHG emissions. For example, if more
people were to switch transport mode, from cars to public transport or cycling they could make very
large savings in their personal energy consumption and hence reduce emissions. Of course, the ability of
people to make such changes depends on many factors, such as how far they live from work. But if such
changes encourage people to live closer to work, they could reduce their emissions further. Indeed
basing more of our economy on local activity, eg buying locally-produced food or other goods and
services, could reduce GHG emissions quite substantially.
The two main options for responding to the risks of climate change involve mitigation—reducing and
eventually eliminating human-caused emissions of CO2 and other greenhouse gases (GHGs)—and
adaptation—reducing the vulnerability of human and natural systems to changes in climate. As a
mechanical engineering we can make a better machinery.
Environment & Sustainability
From the atmosphere to ground water and everything in between, mechanical engineering is essential
in the advancement of environment and sustainability studies. Mechanical engineers work on air and
water pollution, sea water desalination, engine efficiency, alternative fuels, biodegradables, and more to
combat climate change and work toward a greener future.