An Analysis of Conflict and Cooperation Dynamics over Water Events in the Lancang-

14 Riparian countries have their respective values and priorities for water management, and 15 their values of shared water often has possible impacts for their propensity to involve in 16 cooperative management and adhere to treaties/agreements. Improving transboundary 17 water management therefore firstly requires nuance understanding of the changing values 18 and interests of each riparian country to better understand factors that encourage and 19 discourage changes toward cooperation or conflict. This paper provides understanding of 20 the evolution of conflict and cooperation dynamics in Lancang-Mekong River Basin with 21 in-depth analysis of the perspectives of multiple countries. Newspaper articles were used 22 as a key data source as it provides insights into events reported on by the media that are 23 representative of each country/sector they are published within. The results depict a 24 continual trend of cooperative sentiments towards water events occurring within the region. 25 The six riparian states have had a greater average sentiment score for cooperation than 26 international countries for the majority of the study period showing that the region 27 perceived transboundary water management more positively than global audiences. Except 28 for few outliers, the trend also shows that countries further downstream showed lower 29 cooperative sentiments. Dam infrastructure was often negatively reported, thus, it is likely 30 a major contributor to conflict for the Lancang-Mekong River Basin, while events that are 31 positively reported are those that aid in connecting leaders and project developers between 32 riparian countries including meetings, bilateral and multilateral cooperation and 33 development projects. These findings provide the basis for further revealing the mechanism 34 of cooperation and conflicts through understanding these inherent and diverse perspectives 35 of each riparian country, we can gain an insight into the underlying interests that create 36 conflictive or cooperative environments and ultimately predict and manage 37 cooperation/conflict in transboundary rivers. 38 River, contributing to the overall positive perspective of the region.


Introduction 41
Globally there are 310 transboundary rivers that flow across more than 47% of the world's land 169 that are representative of each country/sector they are published within (Cooper, 2005). Through

Data Retrieval 184
The Lexis-Nexis database was selected to extract newspaper information, which is home to more 185 than 6000 news publications around the world and is among most commonly used news sources 186 in the field of social sciences (Weaver and Bimber, 2008;Racine et al., 2010). Searching scope 187 include both major English regional and international newspapers. Although English is not 188 frequently used in most riparian states, English newspapers are accessible and regularly reach an 189 international audience, and is therefore considered a reference to the government's foreign policy 190 (Curtin, 2012). News articles in these newspapers reflect national interests and political responses 191 that riparian countries want to deliver to the international public.

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The search terms are one of the key determinants of the validity and relevance of the data to be 193 collected. The search terms used in this study, as seen in Table 1, were adopted from Yoffe and 194 Larson (2001) and refined to enable the results to water events along the Lancang-Mekong river 195 related to conflict and cooperation between riparian countries. Specifically, the five block of terms 196 requires articles to be included in the search results must discuss "Mekong" river basin in one of 197 topics indicated below, such as dam, irrigation, pollution, etc. These articles need to discuss the 198 conflictive or cooperative aspects of the events involving at least one of riparian countries. The   from -5 to +5 (Nielsen, 2011). In order to represent the conflictive and cooperative sentiments, the searching scope has limited the articles content to instance of cooperation or conflict that 228 occurs within an international basin involving one or more riparian to that basin. Therefore, the 229 calculated sentiment scores based on AFINN scores ranging from -5 to + 5 was considered being 230 able to reflect the intensity of conflict and cooperation accordingly.

Mekong River Basin 249
Overall, news articles pertaining to water conflict/cooperation events along the Lancang-Mekong 250 River have increased in frequency since 1991. As seen in Figure 3a

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To understand the most concerned topics associated with conflict/ cooperation events, topic 268 analysis was conducted with ten topics identified. It was found that nearly one third of all articles 269 were pertaining to dam infrastructure, implying that this is a significant topic that countries have

Conflict and Cooperation Dynamics as Perceived by Each Country 313
Sentiment scores for each country was calculated to reveal detailed insights into the evolving 314 perspectives of each country, as seen in Figure 6a. It was observed that from 1991 to 2018 there 315 is an apparent trend in increasing cooperative sentiment scores for both international and regional 316 publications (Figure 6a). There has also been decreased variability in the average sentiments over 317 time, both international and regional newspaper articles had a similar sentiment score between

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There is also a likely decline in the percentage of positive articles due to the fact that the Lower 382 Mekong Basin countries were experiencing civil and regional wars throughout the 1970s to

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This study also differentiates between international countries and regional countries in how each 387 topic is perceived by the media differently, whether riparian is over-critical of water events or https://doi.org/10.5194/hess-2020-390 Preprint. Discussion started: 17 August 2020 c Author(s) 2020. CC BY 4.0 License.  water* or river* or lake* or dam* or stream* or tributar* or diversion* or irrigati* or polluti* or "water quality" or flood* or drought* or channel* Includes at least one of the following words related to conflict/cooperation: treat* or agree* or negotiat* or resolution* or commission* or secretariat* or "joint management" or "basin management" or "peace accord" or settle* or cooperat* or collaborat* or dispute* or conflict* or disagree* or sanction* or war* or troop* or "letter of protest" or hostil* or "shots fired" or boycott* or protest* Includes at least one of the following words related to countries involved: Thai* or Cambodia* or China or Chinese or Lao* or Myanmar* or Burm* or "viet nam" or Vietn* Does not include any of the following words: sea, ocean, navigation, nuclear, "water cannon", "light water reactor", "mineral water", "hold water", "cold water", "hot water", "water canister", "water tight", "water down", "flood of refugees", oil, drugs  Step 4:

Topic Analysis
Step a: Pre-process data using TextProcessor and readCorpus to remove stopwords, integers, punctuation and refining all words to their roots word through stemming Step b: Using Structural Topic Modelling Packages, the top 10 main topics were extracted from articles within each year Step c: Find the proportion of each topic and manually label each topic from the most frequent words generated based on frequent newspaper article topics

Data Visualisation
Excel, Origin, Tableau 3877 Articles for Coding Step a: Pre-process data through Tokenisation to separate sentences into words and phrases(i.e. also removing stop-words, punctuation and intergers) Step b: Join each article to sentiment lexicon to identify words associated with positive and negative sentiments (i.e.cooperation and conflict) Step c: Generate a Data Frame with words from each article associated with a sentiment lexicon and their overall sentiment Step 3：