Environmental degradation has negatively impacted the quality of life in many places around the world. In some countries, water and air pollution cause health challenges, while in other places, deforestation and climate change pose other significant risks. This made us wonder: which countries are the "greenest" in Asia-Pacific? We analysed a range of publicly available data in order to rank countries in the region. The top-ranked countries in list produce less pollution, waste and greenhouse gasses. They also use a greater share of renewable energy, preserve green spaces and have efficient public transport.
Japan was the highest ranking country on our list by far. The country ranked so well due to its highly-regarded train system, efficient energy grid system and limited water pollution. Japan received the highest score for train service from the World Economic Forum. The WEF also reported that just 2.3% of Japan's population is exposed to unsafe drinking water, which was tied for second among countries in our study. The country also ranked well in terms of its adoption of renewable energy (7.8% electric production from renewables) and its electricity grid efficiency (4.1% transmission & distribution losses).
Singapore ranked as the second greenest country in the region, according to our analysis. Singapore has low water and air pollution levels as well as efficient energy and train systems. For example, Singapore's electric grid is the most efficient of any country in our study, with just 1.8% transmission and distribution losses, in terms of total electric power produced. Additionally, the country ranked among the top 5 for air and water pollution statistics. Singapore could improve by increasing its renewable energy production, as just 1.8% of its total energy production came from renewables.
3. Australia & South Korea (Tie)
In third place, we have a tie between Australia and South Korea. Australia has very low levels of air pollution (6.8 µg/m³ average PM2.5 concentration) and water pollution (2.2% exposure to unsafe drinking water), both of which were the best in the region. South Korea also very clean water (2.3% exposure to unsafe drinking water), a significant amount of significant green space (63.4% of the country is forested) and a highly regarded train system. Despite their high ranks, Australia and South Korea have relatively high greenhouse gas emissions, ranking 13th and 12th for these categories, respectively.
5. New Zealand
In fifth place, we have New Zealand, which was a leader in a few categories. First of all, New Zealand had the lowest air pollution in its capital in 2018 (6.0 µg/m³ average PM2.5 concentration). It also has the greatest share of renewable energy production (24.6% of total production) and urban green space per capita (207 m2). Despite these positive figures, New Zealand produces the second most plastic waste among countries in our study, with about 0.3 kg per person produced daily.
Where Does India Rank?
India tied for 10th place, with China, according to our research. On one hand, the country produces the least plastic waste per capita (just 0.1 kg daily). India also produces less greenhouse gas per capita than other countries in our study (1.7 metric tons). However, it could improve its grid efficiency (18.6% electric power transmission & distribution losses of total output). Air and water quality are also major concerns for the country, which ranked last for both of these categories in our analysis.
Discussion of Categories
In order to rank countries in Asia-Pacific in terms of environmental friendliness, we selected 7 categories that measure the environmental impact and state of the environment in each country. Our categories include water and air pollution, greenhouse gas (GHG) emissions, waste, forest and green spaces and public transport. Together, these categories help explain the state of the environment as well as human impacts on the environment, in each country.
For our energy category, we ranked countries based on 2 statistics: electricity production from renewable sources (excluding hydroelectric) as a percentage of total energy production and electric power transmission and distribution losses as a percentage of total output. These metrics give us a basic understanding of how much each country has adopted clean energy as well as a picture of the relative efficiency of each country's electricity system. It is important to note that we chose to measure renewable energy adoption without hydroelectric energy. This is because larger hydroelectric dams are known to have life-cycle emissions factors that are more similar to those of fossil fuel-based energy sources, rather than other renewable energy sources. Additionally, hydroelectric dams can cause significant environmental damage to their surrounding ecosystems.
To measure air pollution, we gathered data for the average particulate matter (PM 2.5) concentration in 2018 for each country and its capital city. Using both capital city and country level data allows us to compare urban and overall air quality. Furthermore, PM 2.5 is an important measure of air quality as high levels can be harmful to human health and cause reduced visibility.
In addition to air pollution, water pollution is an important factor in determining the state of the natural environment in a country. To gauge water pollution in each country, we used the prevalence of unsafe drinking water. This was an easily comparable statistics across the countries in our study and is also directly related to human health. For our rankings, we used the World Economic Forum's estimate of percentage of each country's population that is exposed to unsafe drinking water. WEF gives each country a percentage estimate as well as a score based on that rate. Because Hong Kong was only given a score, but not a percentage estimate, we ran a simple regression to estimate the percentage of Hong Kong's exposure to unsafe drinking water.
Greenhouse Gas Emissions (GHG)
Greenhouse gases (GHG) are believed to be the leading cause of human caused climate change. These gases trap heat in the earth's atmosphere, which can accelerate climate change. Therefore, countries that produce less greenhouse gases are relatively more environmentally friendly. We gathered 2 carbon dioxide (CO2) (a common GHG) statistics to understand each country's emissions—CO2 emissions in metric tons per capita and CO2 emissions per unit of GDP. We used both statistics in order to help balance the rankings between countries with very different levels of income and population.
To compare each country's waste, we used a statistic measuring plastic waste. Plastic waste is widely known to be harmful to several ecosystems. Our study ranked countries by kilograms of plastic waste per person per day. We would have liked to also include recycling rates, but this data was not collected in a comparable manner for all of the countries in our study. However, we believe that waste generation is the root of the problem, making it an important statistic to compare.
To analyse the green space of countries in Asia-Pacific we measures that are beneficial to quality of life as well as at capturing carbon emissions. First, we used forested area as a percentage of all land in the country. Forested areas are important as they can capture carbon dioxide, a harmful GHG. We also used square meters of green space per person in each country's most populous city. These green spaces are environmentally friendly for many reasons and make cities appealing to residents.
Finally, we decided it was important to compare public transport in each country. Public transport allows residents to travel in an environmentally manner, compared to driving their own vehicle. We used the World Economic Forum's (WEF) "Effectiveness of Train Services" score as a proxy to compare public transportation systems.
Methodology & Sources
In order to rank the most environmentally friendly countries in Asia-Pacific, we gathered publicly available data for the categories listed above. Once we compiled the data, we created an average rank for each statistic to calculate each country's rank for each category. We determined each country's overall rank by averaging their categorical ranks. By using this process, we weighted each category evenly.
There are several limitations to our study that are worth mentioning. First, due to the complex nature of environmental issues, our simple analysis should not be considered comprehensive. Additionally, it is not intended to inform public policy related to the environment. Instead, our goal is to use a handful of relevant metrics to give a broad characterisation of environmental health and the impact of human activity on the environment by country.
We should also mention that there are some limitations to the data used in our study. First of all, there was not sufficient data for every country in the region, which means that our analysis was limited to 13 countries in the area. Therefore, we focused our article on the top performing countries, rather than highlighting those at the bottom of the list. Similarly, we do not intend for the countries at the bottom of the list to be regarded as the "least green" in Asia-Pacific, due to the narrowed list of countries. Last, we used the most updated publicly available data; however, in some instances the data we used is a few years old. For a full list of sources used in our study, please refer to the table below.