Low-Carbon Transport Policy in Four ASEAN Countries: Developments in Indonesia, the Philippines, Thailand and Vietnam

Emerging countries in Southeast Asia are facing considerable challenges in addressing rising motorisation and its negative impact on air quality, traffic, energy security, liveability, and greenhouse gas emissions. This paper presents a comparative analysis of the approach and status of sustainable, low-carbon transport policy in ASEAN countries and identifies differences and similarities. The methodology is based on a taxonomy of policy components as developed by Howlett and Cashore. The data come from comprehensive country studies for Indonesia, the Philippines, Thailand and Vietnam and interviews with policymakers. We find that each country has a specific set of goals, objectives and targets that support sustainable transport, and, directly or indirectly, climate change mitigation. In terms of specific mechanisms and calibrations, which we analyse based on the Avoid−Shift−Improve approach, there are notable differences between the countries, for example in terms of fuel economy policy. Even though an initial response to climate change mitigation challenges is visible in these countries’ transport policies, much more effort is required to enable a transition to a transport system compatible with long-term climate change and sustainable development targets.


Introduction
The member countries of the Association of Southeast Asian Nations (ASEAN) are experiencing robust economic growth in recent years. This growth has resulted in a rapid increase in the demand for motorised transportation. Southeast Asian countries already face serious problems including congestion, fossil fuel consumption, air pollution and road crashes, while significantly contributing to the ever-increasing global greenhouse gas (GHG) emissions, notably CO 2 and black carbon, as transport accounts for approximately one-quarter of regional final energy consumption [1]. This picture is likely to get worse with vehicle registrations increasing by over 10% annually in many countries [2] and

Theoretical Framework for Low-Carbon Transport Policy Analysis
In his seminal work on policy development as a process of social learning, Hall [16] decomposed policy into three distinct elements or variables: the overarching goals that guide policy in a particular field, the techniques or policy instruments used to attain those goals, and the precise settings of these instruments (p. 278). These components can change at different speeds, with change in settings, instruments and goals referred to as first, second and third-order change respectively. Building on Hall's work, Howlett and Cashore [17] developed a more elaborate taxonomy of policy components. At the level of ends and aims, they distinguish the goals, which are the ultimate ends and general ideas that policy development is trying to achieve; objectives, which operationalise the goals into formal policy aims; and settings, the more specific requirements specified in the policies or measures. At the level of policy means and tools, the components are divided into the instrument logic, referring to the general norms that guide the choice of the mechanisms or specific instruments, and the calibrations, or the specific ways the instruments are used.
In transport policy analysis, Howlett and Cashore's taxonomy has been used in various articles. In their analysis of transport policy change in the United Kingdom, Marsden et al. [18] observe changes in calibrations and the types of instruments being deployed to respond to the need to address climate change, however paradigmatic change has not taken place. Bache et al. [19] argue that climate change mitigation policy can be seen as a meta-policy in relation to transport policy. They found the impact of climate change objective on transport policy "symbolic" for the UK, in other words, having a minor impact on the ground. In addition, the aforementioned study [15] (p. 9) found that "the majority (60 papers) focused on the 'means or tools' components of policy: the instrument logics, mechanisms and calibrations, with only four of them focused on the 'ends or aims' of policy; the goals, objectives or settings".
Before we explain in Section 3 how Howlett and Cashore's taxonomy is applied in this study, we briefly discuss concepts of sustainable transport policy. Over the past decades, shifts in approaches and frameworks for transport policymaking have taken place in the context of sustainable development. Such changes include the shift away from "predict−provide−manage" to "provide−predict" [20], a renewed emphasis on transport indicators such as accessibility, quality of life, equity and justice [21] and interventions aimed at improving these, such as transport demand management [22,23] or people-focused policy development [24]. There is an emerging consensus among scholars, international organisations and governments that in addition to the contribution transport makes towards economic and social development, its negative impacts on society need to be minimised to move towards sustainable transport [25]. The climate change policy agenda, in particular the notion that dangerous climate change cannot be avoided without deep GHG reductions in the transport sector, is one key driver for thinking on sustainable transport policy. It is also widely acknowledged that sustainable transport is essential in realising the Sustainable Development Goals [26] and that reducing GHG emissions from transport yields important sustainable development benefits at the local and national level [27]. These benefits, rather than climate change per se, are often stronger arguments for decision makers for sustainable transport policy, particularly in developing countries.
One policy approach to addressing GHG emissions and other environmental impacts of transport is captured in the so-called Avoid−Shift−Improve (ASI) framework [28]. In this framework, low-carbon transport policy needs to cover measures aimed at: (a) avoiding the need to travel, e.g., by improved urban planning, travel demand management or road pricing, and e-communication options (mobile phone use, teleworking); (b) shifting travel to the most efficient or clean mode, e.g., non-motorised or public transport; and (c) improving the environmental performance of transport through technological improvements to make vehicles more energy efficient and fuels less carbon-intensive (see also Appendix A). Bakker et al. [25] argue that, to bring the ASI approach closer to a practical guide to sustainable transport policy, "access" needs to be added to cover the positive impacts of transport as well as elements of sustainable lifestyles and transition thinking, the latter based on, e.g., Geels [29]. An analysis of transport transitions and experimentation concludes that in Thailand, sustainable transport niches do not (yet) challenge the dominant regime of motorisation [30].

Methodology and Materials
In carrying out the comparative policy analysis, we apply concepts of low-carbon transport policy and policy components based on Howlett and Cashore's taxonomy. It is noted that our interpretation is close to that of Marsden et al. [18], although there are differences in operationalisation for some components, particularly the instrument logic. Table 1 explains how we operationalise their framework for low-carbon transport policy, which will be used in Section 4. Goals are related to overall development objectives as well as those for the transport sector and are derived from visions in development plans and sectoral transport strategic documents. Objectives are more specific aims of transport policy as stated in transport strategies and plans. In addition, we consider as objectives the Nationally Determined Contributions (NDCs) submitted to the United Nations Framework Convention on Climate Change (UNFCCC) in 2015 [31]. These include country-wide emission reduction targets and thereby can be seen as "meta-policy" objectives [19] that are relevant to the transport sector. The settings are the quantified targets related to those objectives. While there is often a plethora of such targets, we selected those directly or indirectly related to climate change mitigation (if available): GHG emission reduction, public transport modal share, energy efficiency, renewable or alternative energy or energy diversification, and limitation of motorisation.
The instrument logic is based on two aspects. First, we look at specific features or aspects in strategic policy documents that could be indicative of the background of policy directions, such as those related to vehicle manufacturing industry development and mentioning of "lifestyle" issues. It is noted that there may be a subjective element here, and our data are not necessarily comprehensive. Second, we consider the use of ASI as a policy framework in strategic documents: it can be argued that its use-explicitly or implicitly in the instruments being deployed-may indicate an understanding with policymakers that a comprehensive approach to sustainable transport including changing behaviour is required. For mechanisms and specific instruments, we use a comprehensive inventory (explained below) of low-carbon transport policies and measures in each country as organised in the ASI framework. In Table 3, we summarise the main sets of instruments with the highest relevance to carbon reduction. We also examine if and how countries are making use of international climate change instruments for the transport sector, in particular nationally appropriate mitigation actions (NAMAs), the Clean Technology Fund of the World Bank and other multilateral development banks, and the carbon trading instrument Clean Development Mechanism. Finally, as we cannot cover calibrations for all low-carbon transport measures, we provide examples for three types of measures that are important for climate change mitigation, but that are differently used across the four countries: specific measures in transport demand management, promotion of cycling and fuel economy of new vehicles.
The choice of the four countries is based on three sets of considerations, starting from the observation that sustainable transport policy in Southeast Asia is an under-researched topic yet relevant e.g., based on the ASEAN Transport Strategic Plan [3]. First, the countries constitute four of the five largest transport sector GHG emitters of the region [32]. Second, they have characteristics that set them apart from many other countries-particularly North America and Europe-including rapid motorisation, lower current urbanisation but rapid growth of megacities, higher urban density, importance of informal transport sector including paratransit, high modal share of motorcycles, inadequate and hierarchically unbalanced infrastructure, high but decreasing share of public transport (except Vietnam), lower government revenue and lack of private sector financing, and weak land-use control [8]. Third, they have differences amongst them in other aspects including culture, economic development, economy structure, governance systems, geography and roles of actor groups. These could help in explaining differences that may be found (see also Section 5). In addition, a more practical consideration was that data on policy development in these countries were readily available to the author team.  Table 2 shows a set of indicators that help describe the context of transport and climate change policy in the four countries, using secondary data from a range of sources. Out of a larger set of possible indicators, we have limited ourselves to those that provide key information on the transport system, particularly related to climate change, and those that are arguably relevant in explaining differences between countries.  [34], c [35], d [12], e [2], f [36], g Adapted from [37], h [38], i [39].
The lowest and highest per capita incomes differ by a factor of three, yet all countries are rapidly motorising-in line with global trends for vehicle ownership in low and middle-income countries [40]. The growth rate for cars is higher than for motorcycles, however the latter still dominate the vehicle fleets. It could be expected that the share of motorcycles will decrease over time as income levels grow [41]. Thailand has the highest rate of passenger cars per 1000 inhabitants, of which a significant share are domestically manufactured pick-ups with relatively low fuel efficiency as compared to sedans [42], which explains the relatively high per capita transportation emissions. Biofuel blending targets are present in all countries for biodiesel and/or ethanol [11].
The data used in the analysis in Section 4 were collected through a literature survey and studying the contents and context of national and local policy documents-many of which in the local language-as well as through semi-structured interviews [43] with key informants. Five interviews with policymakers from the four Ministries/Departments of Transport and two with transport researchers were held on the sidelines of various transport workshops and meetings. The interviews provided insights into the institutional structure, the development of policy documents, as well the role of different policy objectives, including climate change mitigation, in policy development. Feedback from policymakers and academics was gathered in workshops and in writing, and draft results were discussed in a workshop with representatives from all four countries. The results are included in four country studies, named Stocktaking Reports on Sustainable Transport and Climate Change for Indonesia [44], the Philippines [35], Thailand [45] and Vietnam [46]. These studies review the existing sustainable transport policy framework and key policy documents and related sources that include strategies, policies or measures with a direct or indirect impact on energy use and CO 2 emissions from transport, resulting in an inventory of policies and measures for each country, organised along the ASI approach (see Appendix A). For Thailand and Vietnam, additional literature and policies that were developed since publication of the Stocktaking Reports in 2014 and 2015 were reviewed for this article.

Results: Low-Carbon Transport Policy Components
In Table 3, we provide an overview of policy components related to sustainable (passenger) transport and climate change mitigation for the four countries, following the methodology introduced in Section 3. When policy components are relatively similar for all four countries, we use merged cells. As noted in Section 2, sustainable transport is a wider concept than just low-carbon transport. However, most measures taken to promote sustainable transport will reduce greenhouse gas emissions. We assume (confirmed in multiple interviews) that most of the policy ends and tools are developed by policymakers for local and national sustainable development objectives such as congestion reduction, efficiency, comfort, safety, rather than climate change. Therefore, for the analysis this paper it is deemed useful to consider sustainable transport policy.
Looking at the level of policy goals, we observe that sustainable transport appears to support various high-level national development goals, such as inclusive growth, sufficiency economy, people-oriented development. Visions in transport strategies acknowledge the need to be environmentally-friendly, and in some cases explicitly mention climate change or energy issues. In general, improving connectivity and transport infrastructure is the key goal in transport strategies, with "accessibility" included in policy documents in Thailand [47] and Indonesia.
Each country has a set of objectives for the transport sector, which include climate change mitigation explicitly for two countries, however indirectly, through other objectives such as increasing public transport and energy efficiency, all countries address low-carbon transport. The same is true for the settings: all countries have quantified targets related to sustainable transport (e.g., public transport modal share, energy self-sufficiency, GHG emission reduction); however, these targets are different in nature and in the way these are formulated. When considering the NDCs, which for all countries include quantified GHG emission reduction targets for 2030 compared to business-as-usual, we observe that the transport sector is included, even though the level of ambition and detail differs from a minor mention as part of the energy sector (Indonesia) to concrete actions (Vietnam) [32].
In support of the NDCs (also part of settings), the Biennial Update Reports and overall climate change policy, countries are carrying out initial mitigation potential analysis and developing climate mitigation scenarios (e.g., for 2020 or 2030). In connection to these and other policy processes, stakeholder dialogues around the required, desirable and feasible changes in the transport systems, are held. However, a comprehensive approach going beyond incremental improvements appears to be lacking, and the scenarios are mostly based on existing policies, leading to emission savings compared to a reference scenario, but not yet in a stabilisation or absolute reductions in emissions. Long-term (e.g., 2050), ambitious scenarios to achieve deeper carbon reduction in line with global climate change goals [12], and visions on what low-carbon transport should be and which technologies and changes in the transport systems are required, are not yet developed by national governments. The need for a "transition" or transformational change, and changes in behaviour and lifestyle are discussed in a limited fashion (e.g., in Vietnam).  In terms of the instrument logic, it should first be noted that, to improve sustainability in the transport sector, a large set of policies and measures can be deployed (see Appendix A). Indeed, we find that the four countries are using or considering the majority of these options, which cover economic (including public investments), regulatory (including planning) and information instruments. In many cases, a combination of instruments is used to achieve a similar objective such as improving vehicle energy efficiency. Further research would be required to be able to draw conclusions on long-term preferences for types of instruments, if at all such statements are possible for the transport sector as a whole. That said, some initial observations may include that the government aims to play a role in behaviour change and limiting motorisation in Vietnam and Indonesia, and in the Philippines with the number coding scheme. The electric vehicle roadmap in Thailand, which focuses predominantly on the vehicle production side, could be indicative of the key role of economic development versus other policy drivers. We should note however that these are merely examples, and it cannot be concluded that in the other countries the situation is fundamentally different. In relation to this, the absence or relatively low level of fuel taxes for both petrol and diesel for all countries could be seen as a sign that limiting the use of private vehicles is considered difficult or not necessarily a shared objective among stakeholders. In the instrument logic component, we also look at the ASI approach, which is used explicitly in policy documents on environmentally sustainable transport or climate change in two countries, however it does not appear in the main transport development strategies. ASI therefore may not play a major role as a policy concept yet. As it has only become well-known in recent years [25], it would be premature to draw conclusions from this observation. Nevertheless, all four countries are developing or implementing measures in each of the ASI categories.
When looking at the mechanisms, many of the Shift and Improve policies included in [12] are being developed and implemented in the four countries, even if not yet sufficient in ambition. The Avoid policies such as transit-oriented development, road pricing, parking and vehicle restrictive policies are essential in meeting long-term targets [12], however are in an early stage of development or missing. In this context, Han [52] also notes that "fast developing countries are at a crossroad in transport policy development", and current policies may not be sufficient to avoid a lock-in into high-carbon, unsustainable transport based on individual motorised transport.
There are also notable differences in calibrations, e.g., for fuel economy policies, with Vietnam (labelling and standards) and Thailand (CO 2 -based vehicle excise tax) having more advanced policies than the other two countries. On the other hand, Philippines and Indonesia employ transport demand management such as number plate-based vehicle restrictive measures.
A final observation concerns institutional development in the connection to transport and climate change. This is an aspect that may not fit in well with Howlett and Cashore's taxonomy that focuses on policy content, however could be indicative of the development of policy ideas [53] and thereby relevant for low-carbon transport policy. In response to climate change and other environmental issues, all four countries have set up specific institutions in their ministries of transport. These include climate change and sustainable transport committee (Thailand), a transport technical working group in the climate change council (the Philippines), a Department of Environment (Vietnam), a Center for Sustainable Transport Management (Indonesia) and an Environmentally Sustainable Transport Unit (the Philippines). Even though the number of full-time staff is currently limited (eleven in Vietnam for example, in the other countries fewer), emergence of these institutions shows the growing relevance of climate change in transport policy.

Discussion
In this section, we first reflect on the methodology and then consider explanatory factors related to the findings in the comparative analysis.
Application of the policy component taxonomy of Howlett and Cashore to sustainable transport policy was possible after interpreting and operationalising it for our purpose, and yields insights into similarities and differences between ASEAN countries. Its benefit lies in the consideration of multiple components relevant for policy, which may not have become apparent without using it. For example, we could observe that the components of sustainable transport policy at the level of policy ends (goals, objectives, settings) are not consistently matched with the currently applied tools (instrument logic, mechanisms, calibrations) to achieve these.
We however note several methodological challenges as well. First, tackling climate change in the transport sector is a complex problem and requires simultaneous implementation of policies and measures in the realm of mobility (Avoid and Shift) on the one hand, and vehicles and fuels (Improve) on the other. All of these can be taken with a view to a wide range of different policy objectives (see Table 3), with climate change mitigation being only one of them. Assessing the current situation in a comprehensive manner, and assessing progress in the future, is therefore challenging. This is particularly the case when describing the mechanisms and the calibrations, for which we could only show three examples out of a much larger set of options, due to space limitations. Dupuis and Biesbroek [54] appear to suggest a similar approach-i.e., based on selected examples-for assessing policy change in climate change adaptation. Second, the presence of long-term quantitative scenarios for low-carbon transport was considered in connection to "settings", however this could also be seen as being part of "goals". Third, assessing the instrument logic poses methodological challenges and since our data are limited and we chose to report specific examples from each country, implying a level of subjectivity. Finally, we consider institutional development specifically for sustainable transport and climate change a relevant aspect of policy even if not a component of policy content per se.
The framework offered by Howlett and Cashore is useful for taking stock of sustainable transport policies in the four countries, however their categorisation does not explain the content and character of those policies nor differences between the countries. Although not a core aim of this article, we will now explore possible explanatory factors for the trends and differences found between the four countries. We will do so in an inductive way, i.e., starting from our research findings we will flag up possible explanatory factors and suggest links to the broader literature. It is duly noted this is rather challenging due to the complex array of factors influencing transport policy, the large number of possible options in the sector, as well as our data limitations. A more systematic explanatory analysis is beyond the scope of this paper.
When it comes to fuel economy policy instruments and calibrations (see Table 3), different approaches appear to exist in countries with (Thailand and Indonesia) and without (Vietnam and Philippines) a large domestic car manufacturing industry (see Table 2). Vietnam was the first country to implement labelling for all new passenger cars, while Thailand and Indonesia provide incentives for smaller cars and Thailand exempts larger pickups from the incentive scheme, which benefits domestic manufacturers. "Limiting motorisation" as a policy objective and/or implementation of vehicle restriction measures was found in three countries, although the relatively low fuel taxes (calibration), found in all four countries, may not support this objective. While no firm causal relationship can be established from our data, we could theorise that policy coherence [19,55], i.e., the use of policy means and tools based on consideration of different and potentially conflicting [44] policy ends and aims (see Tables 1 and 3), may be a factor influencing transport policy instruments and calibrations. In other countries, "industry promotion" was also found (e.g., in Vietnam, based on interview) to be a policy objective. As Kivimaa and Virkamäki [55] note, "established regimes not only for transport but for energy and industry, i.e., multi-regime interaction" are relevant to low-carbon transitions, which require coherence in policies in different sectors.
Local stakeholders are also relevant factors. For example, non-motorised transport policies such as those for cycling appear to be more developed in Thailand and the Philippines, in the development of which an advocacy role for civil society groups was observed [56], although in transport policy development in general non-governmental organisations are important in Indonesia as well [44]. Aside from local stakeholders, international organisations and processes such as ASEAN meetings, UNFCCC conferences and the UNCRD Environmentally Sustainable Transport Forum are likewise relevant. Such meetings (according to three interviews with policymakers) appear to influence policymakers in transport agencies who develop strategies and action plans. Howlett et al. [53] consider them policy entrepreneurs by their way of using policy windows to put issues on the policy agenda. Whether other factors, such as cultural values and orientations [57], political systems and decision-making processes [51], income levels and professionalism of legislature [58] are relevant in low-carbon transport policy development would require more analysis. In such research, the design should include a list of possible factors and clearly defined policy outcomes as the dependent variable.
In addition, we consider to what extent climate change objectives are relevant for transport policy. In all countries, we observe that the transport sector is included in climate change action plans as one of the key sectors that should contribute to the national mitigation objectives as included in the NDCs. As to the question whether climate change objectives have a real impact on transport policy development and implementation, i.e., whether it is symbolic [54], there is evidence from one country (Indonesia, based on interviews) that the climate change objectives and sectoral action plans provide additional arguments or drivers for national and local transport policies, i.e., it can create new windows for policy entrepreneurs to influence the transport policy agenda. For other countries, we could not find direct indications for such windows. In all four countries, mitigation actions (NAMAs) are developed in the transport sector, however none of these are implemented yet, hence no impact on transport policy can be observed yet. Therefore, although we consider it possible that climate change mitigation is more than a "symbolic" meta-policy, more research is required to test this hypothesis.

Conclusions
Countries in Southeast Asia are experiencing rapid growth in motorisation and associated negative impacts on congestion, air quality, road safety, energy security, urban liveability, and greenhouse gas emissions. To be compatible with sustainable development and climate change objectives, significant change is required. This article has shed light on the policy developments in four ASEAN countries in this context: Indonesia, the Philippines, Thailand and Vietnam. When looking at the current transport system, the countries are relatively comparable in some aspects such as the importance of motorcycles and vehicle fleet growth rates, while there are substantial differences in motorisation levels and per capita transport CO 2 emissions. These can only partially be explained by the variation in income levels.
When looking at the current status of policies on sustainable transport and climate change, we found several common elements across the four countries. First, at the level of policy ends, each country has a set of goals, objectives and specific targets or settings in policy plans and strategies that support sustainable transport, and, directly or indirectly, climate change mitigation. Second, looking at the component of policy mechanisms, all four countries are active in development of nationally appropriate mitigation actions in the transport sector. In the realm of transport demand management and "Avoid" strategies, policies and measures are in an early stage of development or absent. Shift and Improve measures are generally more developed. Third, the policy ends are not always consistently matched with the policy tools.
There are notable differences as well: (i) a policy objective to limit motorisation was only found in two countries, while the others do not address this explicitly; (ii) as part of the instrument logic, the Avoid−Shift−Improve approach is used in transport policy documents in two countries, however as yet it does not appear to have major importance as a framework to structure and develop policies; and (iii) with regard to policies to improve vehicle fuel efficiency, the use of different policy mechanisms and their calibrations vary strongly from one country to the other.
Although climate change mitigation is generally of lower concern for transport policymakers compared to improving efficiency of the transport system and reducing local impacts, we found significant attention to the climate change agenda. First, climate change is addressed in key transport policy documents and is becoming relevant as a policy driver; and, vice versa, transport plays a role in climate change policies. Second, institutions are being set up to specifically deal with transport and climate change. Finally, our policy review also shows that a range of ASI policies are being discussed, developed or implemented, which could result in significant emission savings compared to business as usual. However, stabilisation or an absolute reduction in GHG emissions from transport is not likely in the near future, nor are long-term plans in place that enable a transition to climate-compatible transport development.
With regard to policy research, we found that applying the taxonomy of policy components of Cashore and Howlett can readily be applied to structure the comparative policy on sustainable transport in ASEAN countries. The analysis results in relevant insights into similarities and differences in policy emphasis. Future research using this framework could be carried out to observe changes in low-carbon transport policy, both at the national and urban level. Other research topics include the role of institutional development and transport policymaking process. Finally, it would be relevant to know how climate change can be better reflected in and used as a driver for transport policy would be relevant in connection to the transformational change required in transport policy in order to meet long-term climate change objectives.

Conflicts of Interest:
The authors declare no conflict of interest. The founding sponsors had no role in the design of the study; in the collection, analyses, or interpretation of data; in the writing of the manuscript, and in the decision to publish the results.