Acid Deposition Monitoring Network in East Asia (EANET)

Due to rapid economic growth, urbanization, and industrialization, many countries in East Asia are facing a serious threat from air pollution, including acid deposition. Since acid deposition is transboundary in nature, which can occur at a substantial distance from the original sources of emissions of acidic substances, regional cooperation and collaboration are essential to address the acid deposition problem in the region.

Major primary air pollutants emitted directly from sources which are prevalent in East Asia are sulfur dioxide (SO2), nitrogen oxides (NOx), particulate matter (PM), volatile organic compounds (VOCs), carbon monoxide (CO), and toxic elements. Major sources of these air pollutants are automobiles and industries.

Secondary air pollutants formed by atmospheric reactions of primary air pollutants and also prevalent in East Asia are photochemical oxidants, including ozone (O3), and secondary aerosols.

SO2 and NOx are transformed by chemical reactions with air constituents into sulfuric and nitric acids which are transported and deposit to the earth surface far from the emission sources, the so-called “Acid Deposition”. The acid deposition, realized in two types of processes known as wet deposition and dry deposition, can cause impacts to ecological systems and human health. Various countries in East Asia have worked together since early 1990s to establish the Acid Deposition Monitoring Network in East Asia (EANET).

 The objectives of the EANET are (i) to create a common understanding of the state of acid deposition problems in East Asia; (ii) to provide useful inputs for decision-making at the local, national, and regional levels aimed at preventing, or reducing adverse impacts on the environment caused by acid deposition; and (iii) to contribute to cooperation on the issues related to acid deposition among the participating countries. The participating countries agreed to promote the establishment of a regional monitoring network on acid deposition based on a step-by-step approach aiming at monitoring acid deposition in East Asia on a regular basis. The tentative design of the Acid Deposition Monitoring Network in East Asia (EANET) which is essential for the successful operation of the network was developed at the First Intergovernmental Meeting on the Acid Deposition Monitoring Network in East Asia held in Yokohama, Japan in 1998.

The First Intergovernmental Meeting also agreed as the first step to implement activities of the EANET on an interim basis as a preparatory phase aiming to start monitoring activities of the EANET on a regular basis in the year 2000 at the Second Intergovernmental Meeting taking into account experiences accumulated during the preparatory phase. The preparatory phase of the EANET was then implemented for a period of two years starting from April 1998 to 2000.

The Second Intergovernmental Meeting on the EANET held in Niigata, Japan in October 2000 issued the Joint Announcement on the Implementation of the EANET in order to cooperatively start the activities of the EANET on a regular basis from January 2001 with 10 East Asian participating countries, and later expanded to 13 countries, namely Cambodia, China, Indonesia, Japan, Lao PDR, Malaysia, Mongolia, Myanmar, Philippines, Republic of Korea, Russia, Thailand, and Vietnam. Major activities of the EANET include (i) acid deposition monitoring; (ii) compilation, evaluation, storage, analysis and provision of data; (iii) promotion of quality assurance and quality control activities; (iv) implementation of technical support and capacity building activities; (v) promotion of research and studies related to acid deposition and air pollution problems; and (vi) promotion of public awareness activities. The EANET monitoring covers five environmental media, namely wet deposition, dry deposition, soil and vegetation, inland aquatic environment, and catchment.

At present, there are across East Asia 99 deposition monitoring sites (54 and 45 wet deposition and dry monitoring sites, respectively) and 58 ecological survey sites (20 soil survey sites, 18 forest/vegetation sites, 18 inland aquatic environment (lakes/rivers) sites, and 2 catchment scale sites). The institutional framework of the EANET is composed of Intergovernmental Meeting (IG), Scientific Advisory Committee (SAC), Secretariat, and Network Center. The IG is the decision-making body of the EANET whereas the SAC advises and assists the IG with various scientific and technical matters related to the EANET activities. UNEP was designated as the Secretariat of the EANET and the Asia Center for Air Pollution Research (ACAP) located in Niigata, Japan was designated as the Secretariat and the Network Center to provide administrative and technical supports to the EANET, respectively. The implementation of the some Secretariat function has been delegated to the Regional Resource Centre for Asia and the Pacific (RRC.AP), a Centre for Sustainable Development, collaborating with UNEP at Asian Institute of Technology. 

Fore more details on EANET ....

Dr. Supat Wangwongwatana ,
Project Leader and Programme Specialist
Atmosphreic Resources
P: (662) 524-6235