The global scenario of hydrogeochemical research on glacier meltwater: a bibliometric and visualization analysis

In recent years, there has been a rapid increase in scientific research into hydrogeochemical research on glacier meltwater. Nevertheless, systematic and quantitative analyses are lacking to investigate how this research field has developed over the years. As a result, this study is aimed at examining and evaluating recent research trends and frontiers in hydrogeochemical research on glacier meltwater throughout the previous 20 years (2002–2022) and at locating collaboration networks. This is the first global-scale study, and visualization of the key hotspots and trends in hydrogeochemical research has been presented here. The Web of Science Core Collection (WoSCC) database aided in the retrieval of research publications related to hydrogeochemical research of glacier meltwater published between 2002 and 2022. From the beginning of 2002 till July 2022, 6035 publications on the hydrogeochemical study of glacier meltwater were compiled. The result revealed that the number of published papers on the hydrogeochemical study of glacier meltwater at higher altitudes had grown exponentially, with USA and China being the main research countries. The number of publications produced from the USA and China accounts for about half (50%) of all publications from the top 10 countries. Kang SC, Schwikowski M, and Tranter M are highly influential authors in hydrogeochemical research of glacier meltwater. However, the research from developed nations, particularly the United States, emphasizes hydrogeochemical research more than those from developing countries. In addition, the research on glacier meltwater’s role in streamflow components is limited, particularly in the high-altitude regions and needs to be enhanced.


Introduction
The glacier meltwater dissolved ions are influenced by various factors, including the interaction of water and rock, the catchment area's lithology (Kumar et al. 2018a, b;Sharma et al. 2022), and the hydrology of the catchment area and atmospheric sources. This interaction is essential to determining the meltwater quality draining from glaciers (Mitchell and Brown, 2007;Kumar et al. 2019a, b, c). Significant ions in glacial meltwater show that chemical weathering occurs below the glacier environment (Reynolds and Johnson, 1972;Raiswell, 1984;Hasnain and Thayyen, 1999;Kumar et al. 2019a, b, c). The chemical weathering of bedrock in glacier environments occurs when meltwater flows at the rock-ice contact. This process is primarily determined by the glacierized region's geology and climate conditions, such as temperature and humidity (Singh et al. 2020;Bisht et al. 2018;Kumar et al. 2019a, b, c). According to Kumar et al. 2018aKumar et al. , b, 2019a, c, the fluctuations in solute content that occur throughout the year in meltwater are most likely caused by the different intensities of hydrogeochemical weathering at various values of glacial runoff . The varied amounts of meltwater discharge from glaciers influence the composition of the river's various solutes and the river's dissolved load, changing the water's hydrochemistry and quality (Sharma et al. 2019;Kumar et al. 2022). The growing urbanization and industrialization induce an increasing demand for water resources. Hence, the study on glacier meltwater is essential , as it is the source of fresh water for a large population (Thayyen and Gergan 2010;Kumar et al. 2018a, b). A complete hydrogeochemical analysis would be advantageous to acquire a better knowledge of meltwater quality and provide a foundation for preserving and effectively managing water resources (Qaisar et al. 2018;Pant et al. 2018).
This study is aimed at closing any knowledge gaps identified by including more recent papers that cover a wider variety of subject areas connected to the hydrogeochemical research conducted on glacier meltwater. It enables a quantitative bibliometric review combined with a qualitatively structured assessment. Further, it helps to quantitatively evaluate the scientific literature and gain knowledge of the parallels and divergences between the various studies. This review uses the most recent bibliometric analysis methods in conjunction with a structured review to conduct an in-depth investigation into the hydrogeochemical research on highaltitude glacier meltwater from the perspective of multiple and combined paradigms. It covers a quantity that has never been looked at before and uses textual analysis techniques to expand the amount of originality it possesses. Bibliometric analysis is a well-known, practical, and systematic methodology to evaluate the effectiveness of scientific output using mathematical and statistical techniques (Ellegaard 2018;Li et al. 2018). The findings of bibliometric studies have the potential to offer objective perspectives on the scientific productions present in each study field and to offer adequate support for the subjective perceptions held by researchers. This methodology has been used in various study domains to evaluate and forecast scientific production, development, and future trends (Cuccurullo et al. 2016;Merigo et al. 2018). A quantitative analysis of bibliometric indicators can show the number of documents, recent issues, citations, and rank to evaluate the qualities of the literature and the thematic influences present in it (Todeschini and Baccini 2016;Chen et al. 2017;Muhuri et al. 2019). In recent years, the availability of potable water has emerged as a critical component in determining the overall quality of life in modern society. Hydro-geochemistry studies have been paying increasing attention to problems, including waterborne infections, a lack of adequate water quality for communities, and contamination in watercourses. However, no publication is available using bibliometric analysis to study the pattern of hydrogeochemical research at glacier meltwater worldwide.
Because there are increasing publications on the hydrogeochemical analysis of glacial meltwater, it is crucial to produce valuable and convincing results using scientific methods like bibliometric analysis. The review offers a thorough bibliometric study of the academic papers on the hydrogeochemical characterization of glacier meltwater published between 2002 and 2022 using the Web of Science Core Collection database. This contributes to helping scientists understand this research topic more thoroughly. The Web of Science (WoS) database was utilized in this study to assess the changing definition of hydrogeochemical research and anticipated global trends. The analysis was based on visualization and bibliometric analysis approaches. This study is aimed at helping future hydrogeochemical research, analyzing the developmental nature of hydrogeochemical research, and discussing the forthcoming research trends. This article presents a quantitative summary of the characteristics of yearly publications. This research is aimed at acquiring information on the present global status of hydrogeochemical examination of glacier meltwater at higher altitudes. It is of the highest necessity to research the performance of themes using bibliometric indicators. This study is to understand future hydrogeochemical research worldwide by examining the developmental character of hydrogeochemical research and emerging trends. Utilizing scientific techniques such as bibliometric analysis, which aids in fostering a deeper understanding of this research problem by scientists, is crucial for producing meaningful and conclusive results. The bibliometric study offers valuable insights into current research trends and hotspots in glacier hydrogeochemistry. This can assist in identifying subsequent research efforts and inform policy and management choices relating to glacier ecosystems and water resources.

Data acquisition and search strategy
The WoS is a robust literature database that can provide reasonable access to bibliometric indicators of published items and allow us to study the literature in scientific fields. It does both things by allowing us to search various scientific disciplines. Additionally, the WoS database contains comprehensive citation data for research, including over 20,000 publications like journals, conference proceedings, reports, and books. So, we conducted a bibliometric analysis based on the WoS database. Therefore, we searched for keywords using an advanced search tool (including "all fields") with stars and quotation marks on each keyword. We searched keywords in three combinations (ALL = "water chemistry*" OR ALL = "hydrology*" AND ALL = "glacier*", ALL = "hydrogeochemistry*" AND ALL = "glacier*" and ALL = water chemistry OR ALL = hydrogeochemistry AND ALL = glacier) from the core WoS collection.
We limited the study period from 2002 to July 2022 due to the unavailability of older documents on the WoS database (Gao et al. 2020;Aria et al. 2020). About 6035 publications were retrieved from 2002 to 2022 that match our inclusion 1 3 criteria in plain text and excel format for further analysis. We included all available data and language types in the study from 2002 to 2022. We considered articles on environmental science and technology, environmental studies, water chemistry, hydrochemistry, glaciology, geochemistry physics, and remote sensing for the environment. The documents were retrieved from WoS by considering all inclusion and exclusion criteria and following all the PRISMA methodology steps (Fig. 1). We included the major publications listed under WoS indices, such as Elsevier, Springer Nature, MDPI, Copernicus, Wiley, AGU, Cambridge University Press, Taylor & Francis, American Chemical Society, and Science Press. The documents considered include articles, reviews, data papers, and proceedings.

Analytical method
The analytical methods used for bibliometric analysis include co-word and co-occurrence analysis, network and overlay visualization, factorial and dendrogram analysis, and thematic and scientific mapping. The open-source software used in the bibliometric study is the Visualization of Similarity Viewer (VOS viewer) and the "R package" named the "bibliometrix package." These programs can combine data from multiple sources, including authors, journals, institutions, and countries (Chen, 2006;Liang et al. 2017;Liu et al. 2021). The metrics used included the number of publications, the H-index, the impact factor, the centrality, the frequency of occurrence, and the number of citations. These parameters facilitate identifying excellent individuals or organizations and potential cooperative relationships among researchers in hydrogeochemical research papers on glacier meltwater. A phrase with a high frequency of occurrence over a specific time is said to have an occurrence burst, and a reference with a high frequency of citation over that same time is said to have a citation burst (Chen et al. 2012a(Chen et al. , 2014. Burst keywords and references with citation burst are discovered to suggest research frontiers. This is because they can determine whether relevant academics have invested significant attention to these features at a specific time (Chen, 2006). The use of local polynomial regression was used to identify whether the outputs of publications had reduced or increased over time. Productivity was measured based on the number of publications identifying prolific individuals or groups. Scientific mapping is the spatial representation of keywords and authors of different domains, fields, specialities, and research area units related to each other (Small, 1999). Frequency calculations for the author, document, keyword, document, and country are extensively used  (Merigo et al. 2018;Yao et al. 2018). Numerous studies have used this technique to discover the thematic evolution, developments, scientific production, and trends in particular research realms (Seabra and Caldeira-pires 2020). The basic steps used during the analysis were mentioned in the flow diagram (Fig. 2).

Keywords' performance
A co-word and co-occurrence study may gain insight into the fundamental concepts underlying a specific research subject hotspot. In addition, the co-word analysis is a robust tool for locating and describing the relationships between various study themes (Cobo et al. 2011). The concept of co-occurrence of keywords indicates the overall content of the documents is based on the methodology that underpins co-word analysis. Networking, overlay visualization, and clustering were used to measure the authors' keyword co-occurrences and co-word matrix analysis (Coulter et al. 1998). For keywords performance analysis, we included co-occurrence networking, clustering, and tree mapping of keywords. Network analysis of keywords demonstrated how one keyword was interconnected with other keywords during the study period. There were many network forms presented by different colors. The size of the circle represents the networkforming capacity with other keywords. The green color network is the most dominating group with the keyword's climate change, glaciers, snow, heavy metals, and Tibetan plateau, followed by the blue network with chemistry and hydrology ( Figure S1). These were most dominating keywords that co-occurred most during the study period by various authors (Tranter 2003;Wadham et al. 2010;Yde et al. 2008;Kim et al. 2021;Pan et al. 2022;Kumar et al. 2022). Overlay visualization of keywords represented the importance of keywords over time in specific domains ( Fig. 3). It is generally done in two ways, based on the co-occurrence of keywords used by the author over documents published in the average year and total citation with the average year of document publications with that keyword. Here in this study, we did overlay visualization based on complete citations per year publication of document over that keyword. The colored scale represented the total citations on keywords-related documents. The analysis of keywords co-occurrence can preliminarily identify the research hotspots in this field. The co-occurrence frequency of top 5 keywords are "climate change," "chemical weathering," "glacier," "hydrochemistry," and "weathering." These results illustrate that the hotspots of research in this field are mainly focused on the role of climate change on the hydrochemistry of glacier meltwater.
Tree mapping of authors' keywords represented the frequency and contribution of that keyword in the documents published during the study period. Different colors were used for identifying the keywords. The bigger the box size, the larger the contribution and frequency of that keyword during the study. Climate change with dark blue color had the highest frequency (111) and proportion contribution (10%) in the whole searched documents during the study period . The frequency and contribution of the top twenty keywords are represented in Figure S2. The word "glacier" has a frequency of 95 with a 10% contribution, while word "glaciers" has a frequency of 37 with a 3% contribution. Different authors used these terms separately during their research, but hydrochemistry and hydro-geochemistry were studied less than glaciers (Lin et al. 2017;Lehmann-Konera et al. 2018;Michaud et al. 2020;Sundriyal et al. 2021;Sharma et al. 2021). We have mapped to analyze the trends of topics used in this study from 2002 to 2022. The solid circle's size represents the frequency of keywords, while the blue line represents the timeline during which the keywords are used. Climate change, chemical weathering, Greenland, glaciers, and hydrochemistry were the most trending topics with different term frequencies during the study period (Kaushik et al. 2021;Clifford et al. 2021). Weathering and groundwater showed the longest trendline (2012-2020), while atmospheric deposition had a more significant trendline but less frequent keywords in this study ( Figure S3a). The five critical authors' keywords and their growth over the year are shown in Figure S3b. The keywords' performance in different visualization methods showed that climate change, glaciers, water chemistry, and hydrochemistry were studied extensively (Avak et al. 2018;Kumar et al. 2022;Wang et al. 2022;Siman-Tov et al. 2021;Wu et al. 2022). However, the hydrogeochemistry at glaciers is a less developed keyword during the study. Hence, it has future scope for scholars and academicians to understand better the hydrogeochemistry and related research field.

Authors' occurrence analysis
We used "biblioshiny" of the R package and VOS viewer software to analyze authors' performance during the study period. Authors' performance might be examined through various methods such as co-occurrences, networking, cluster analysis, overlay and density visualization, and scientific mapping. We did overlay visualization analysis for co-author analysis. Overlay visualization was done in two ways, one on the basis of the documents produced by the author, and other on the total citations produced per average document. The size of the colored circle represents the author's frequency, while the color line represents the link between the authors. The author had the largest circle having more considerable link-forming strength. S. Kang and M. Schwkowski were the two authors who showed maximum co-occurrences over the study period, while Z. Polkwoska, E. Barbaro, Z. Hu, F. Yan, K. Koziol, and K. Rajesh were emerging authors in recent years 2019 onward ( Figure S4). However, the overlay analysis based on citations revealed that S. Kang and M. Schwkowski had the highest average of 30 citations, while C. Li, Q Zhang, E. Hood, P. Chen, and Z. Cong had the highest total of 50 citations ( Figure S5). The top author's production over time has been shown in Fig. 4. Kang produced most documents with ~ 10 articles with 80 total citations in 2019, while M. Schwkowski, W. Lyons, M. Tranter, and J. Yde had fewer citations but continued the production trend throughout the study period.

Density visualization
Density visualization is the tool in VOS viewer software for mapping the research unit, such as authors, keywords, affiliations, and countries, based on their co-occurrences and link strength. These density visualizations were used to identify trends, emerging topics, institutions, countries, and authors in water chemistry and glacier-related research (Fu and Waltman 2022). During the analysis, the focus on water chemistry has been shifted toward the hydrochemistry of glaciers, water chemistry of glaciers' lakes, climate change, and hydro-geochemistry of glaciers (Sun et al. 2020;Nawrot et al. 2016;Han et al. 2018;Steinlin et al. 2016). The kernel size represents the co-occurrence capacity and link strength. The different colored groups represent the keywords used together during the study. The density distribution for authors' keywords (a), authors (b), countries (c), and institutions (d) is shown in Fig. 5.

Sankey diagrams
Sankey diagrams are employed to signify the flow in numerous networks and measures. They denote flows, relations, and their evolution with measurable facts. These reflect directed and weighted plots. The amount of the influx weights matches its outward consequences at every node. These are envisioned, and communications can be discovered with the processes. Here, we have used a three-field plot through Biblioshiny to assess the relationship between sources, countries, affiliations, keywords, leading authors, and author-keywords. The diagrams of rectangular shapes are used to denote relevant keywords and authors with various colors. The rectangle size designates the connection among several research units, such as countries, projecting authors, and authors' keywords: the larger the rectangle's size, the more associations between various components (Riehmann et al. 2005;Kumar et al. 2021). We plotted Sankey diagrams with three field plots red, orange, and blue color scales. This represents the relationship between the authors (AU) (brown), author keywords (DE) (orange), and author's affiliations and university (blue). S. Kang in author, climate change in authors' keywords, and institute of Tibetan Plateau Research in the author's university dominated during the study period (AU_UN) (Fig. 6a). Further, it represents

Citation and index-based analysis
Citations help to understand the importance of various research units such as authors, sources, affiliations, and countries. Citation analysis can be done for the most cited author, keyword, journal, and country. We used two fundamental laws widely used in the bibliometric analysis, Bradford's and Lotka's. Bradford's law ranks the source/journal based on the frequency and cumulative frequency value. All the searched sources were divided into three zones based on source frequency. Zone-1, zone-2, and zone-3 have been ranked highly, average, and lowest journals, respectively. Science of the Total Environment and Hydrological Processes ranked 1st and 2nd with 52, 34 frequencies, and 52 and 90 cumulative frequencies, respectively ( Figure S6). Science of the Total Environment (52 articles) and Hydrological Processes (46) contributed 0.05% and 0.04%, respectively, to the published documents (Table 1).
In addition, Lotka's law has been used to check the proportion of the author's contribution to written documents during the study period. Lotka's law is an essential aspect of statistical analysis, and it is important to provide additional context and explanation to ensure that the reader fully understands the implications and limitations of the analysis.  Lotka's law, also known as the inverse-square law, is a bibliometrics and information science principle that states about a small proportion of authors in a particular field or domain producing most publications. The highest percentage of authors' contributions signifies the frequency distribution of scientific production, calculated using the Lotka law. The publishing frequency of authors for this study field was represented by a dotted line ( Figure S7) through Lotka law, indicating the highest publication frequency for one or two articles by authors was more contributing than others. The result suggests that about 3691 authors contributed ~ 0.723% with single publications, 616 contributed ~ 0.121% by double publications, and 266 contributed ~ 0.052 by triple publications in the total searched articles. Similarly, contributions by the top 10 authors' publications have been mentioned in Table 2.
The author' and source's impact has been analyzed in this study. Science of the Total Environment was the most cited source with 1154 total citations and 19 H-index, while S. Kang, M. Schwikowski, and M. Tranter were the most cited author with 1631, 1490, and 552 citations and 21, 22, and 12 H-index, respectively. The highest H-index was for M. Schwikowski (22) followed by Geochimica Et Cosmochimica Acta (21). Impact factor and contribution details for the top 15 sources and authors have been mentioned in Table 3.

Scientific contribution
The scientific contribution is essential to the research process to develop knowledge, scientific quality, and impact on the academic world (Basualdo et al. 2016;Lv et al. 2021;Herrera-Franco et al. 2022). The annual scientific production represents the average number of journal/source articles published annually. The yearly scientific contribution could be calculated for various research units such as keywords, authors, journals/sources, institutions, countries, and languages. We calculated the annual scientific production of the articles per year throughout the study period . The year 2019 was the highest-producing year, with 97 articles contributing 9.16%, and 2002 and 2005 were the least contributing years of total publications during the study (Fig. 7). The figure below depicts less number of articles published in the year 2022 compared to the previous year due to the limitation of this study was limited to July 2022. The significant scientific contribution was document-type research articles, with 1001 contributing the most (94.43%). The English language contributed the most (99.72%), with 1057 articles. The science citation index expanded (SCI-Expended) of WoS was highly indexed during 2002-22  (Table S1) in the searched database. During the examination of scientific production as per the authors' countries, we computed the total contribution by the countries during the study period. The country's production was highest for the USA, with 348 articles contributing 32.83% with a total citation of 6323, while China was the second most producer with 227 articles contributing 21.42% of the study. The citation, average citation, and production frequency are shown in the table (Table 4). The blue color scale represents the production frequency of the country, and the gray represents the absence of articles. The USA and China had the highest productive frequency ( Figure S8).

Collaboration and geographic distribution
In this study, we analyzed the countries' collaboration based on their frequency. During the study period, the USA collaborated almost with all countries that contributed during the study period . The blue color scale represents the number of articles produced by the countries, the gray represents the absence of articles, and the red lines show the association between the countries. USA collaborated with the UK, China, Germany, and India about 67, 52, 43, and 14 times, respectively, while China collaborated with Finland, Germany, and India about 32, 26, and 10 times, respectively (Fig. 8). Water is an essential component for the survival of life on the Earth, and glaciers are the primary source of freshwater. Hence, there is a need for global collaboration to bring up significant studies related to water chemistry, hydrochemistry, and hydrogeochemistry on glacier meltwater.
Collaboration between the countries based on singlecountry and multi-country publications has also been analyzed. The horizontal bar graph represents the collaboration of single and multi-country publications based on the number of documents. The blue represents the single-country publications, and the red line represents the multi-country publications. USA and China were the two  countries that dominated their highest number of collaborations in a single and multi-country framework (Fig. 9). Collaboration between the institutions was also studied in this study. We found that the Chinese Academy of Science has the most prominent circle size, meaning it has the highest collaboration strength, followed by the University of Briston, which produced the highest number of documents during the study period . The number of publications increased from 2017 onwards in all institutions due to their collaboration regarding hydrochemistry-related glacier research (Fig. 10). The collaboration provides a platform for sharing knowledge related to the research field.

Thematic mapping
The bibliometric analysis also includes a significant component known as the thematic mapping analysis. This was accomplished through the use of an open-source "R package" known as the "bibliometrix package," which was constructed by Aria and Cuccurullo (Aria and Cuccurullo 2017). In the process of thematic mapping, two indicators known as Callon's centrality and Callon's density were used to measure the performance patterns of various topics across each subperiod. Callon's centrality revealed the significance of a theme throughout all the searched articles, and Callon's density demonstrated how those themes developed. Fig. 8 Geographical collaboration between countries during the study period . The colored scale represents the frequency of articles produced by countries, and the red lines represent the collaboration strength between the countries Fig. 9 Collaboration between different countries based on single-country publications (SCP) and multi-country publications (MCP) during the study period  A graphical representation was used to illustrate the various topics by plotting the various centralities of Callon on the x-axis and the density of Callon's topics on the y-axis (Fig. 11). The themes that have a high density, as well as a high centrality, have been given the label motor themes. Using motor themes, metaphors were significant, leading to the development of keywords that demonstrated clear connections to other themes.
Motor themes form two clusters: biogeochemistry, Greenland, ice sheet, chemical weathering, ice core, water quality, and climate change. These themes with low density and high centrality were basic and transversal themes that focused on general issues of the research domain. The main basic themes were clustered into two groups: glacier, Tibetan plateau, and permafrost, while the second was weathering, hydro-geo-chemistry, and atmospheric deposition. The theme with high density and low centrality is known as emerging or declining theme. It also showed topics in two clusters, hydrochemistry, stable isotopes, and groundwater in one and Antarctica, glaciers, and Holocene in another. Low density and high centrality were for the niche themes. The most widely distributed niche themes showed two clusters, one with meltwater, Greenland, and iron, while the other with heavy metals, Arctic, and Svalbard. However, water chemistry/hydrochemistry of glacier meltwater is still a limited field having a better future scope.

Thematic evolution and factorial analysis
Thematic evolution analysis checks how the term evolved in different time-sliced zones. In this study, we did a thematic evolution analysis for two different time slice zones, one from 2004 to 16 and the other from 2017 to 22. We incorporated the time slice zones into two distinct time slice zones to analyze the temporal evolution of primary keywords throughout the study period. This time zone division described which keywords evolved in the previous ten years  and which are still in their evolution phase with previously evolved keywords or completely new terms in the recent time zone (2017-22) without any previous existence. It also helps to know whether the keyword has been studied frequently in recent six years. Without this time slice, it was hard to compare the temporal evolution of keywords. The line joining the one-time zone keyword to another time zone keyword represented the linkages and how they evolved with time (Fig. 12). In time slice zone-1, climate change and hydrochemistry were dominating keywords (Fan et al. 2019;Kumar et al. 2019a, b, c), while in the time-slice zone-2, Tibetan Plateau, climate change, and chemical weathering were almost equally dominating keywords (Niu et al. 2019;Bucher et al. 2017;Singh and Ramanathan 2017;Jeon et al. 2021;Clifford et al. 2021;Wu et al. 2020). Then, we did the factorial analysis for the authors' keywords used during the study period.
Four groups were formed during the factorial analysis of the authors' keywords. These four groups were developed based on multiple component analysis for conceptual mapping the authors' keywords used during the study period. The pink color on the map represented the most dominating group, while the other three groups were less prominent during the study period (Fig. 13). There is a gap between the studies for water chemistry, hydrogeochemistry, and glaciers that need to be studied more to get better information about how these keywords related to research explored further.
Dendrogram analysis was also done for the authors' keywords. In this analysis, five hierarchical groups of keywords are formed, represented by the five different colors in Fig. 14. The hierarchical clustering-generated order and connections between the keywords are shown in brown. The vertical lines and cuts in the graphic make it easy to examine and make sense of the various clusters. Snow, glacier, and arctic were the single keywords studied alone during the study period, represented through different colors. Brown and orange-colored groups of keywords in the dendrogram were studied most in similar periods. The dendrogram height represents the temporal evolution of keywords during the study period. The brown cluster having keywords meltwater chemistry, water chemistry, Antarctica, weathering, and glaciers was studied in recent times, forming a low height hierarchy than other keywords (Singh et al. 2016;Hodgkins et al. 2013;Yapiyev et al. 2021;Barkdull et al. 2021).

Conclusion
This study has been done globally to identify and quantify the scientific production and importance of academic research on the hydrochemistry of glacier meltwater. During the bibliometric analysis, we have done the networking, co-word analysis, scientific production calculation by factorial and dendrogram analysis, thematic and scientific mapping, and component analysis. VOS viewer and "R package" named as "bibliometrix package" is open-source software used for bibliometric analysis. The criteria employed were the number of publications, the H-index, the impact factor, the centrality, and the citation explosion for each author, journal, institution, and country. Using these criteria, researchers in the hydrogeochemical study of glacier meltwater can more easily identify notable individuals or institutions and explore collaboration opportunities. The results represent that the hydrochemistry and hydrogeochemistry of surface water and groundwater in downstream regions are well documented.
In contrast, the cryospheric region or hydrochemistry of glacial meltwater at high altitudes is less significant. In this study, climate change, chemistry, glacier mass balance, basin hydrology, and hydrochemistry are the most frequently used keywords with the highest global contribution from 2002 to 2022. The most productive authors were from USA, China, and England and globally collaborated with the highest contribution during the study period. Thematic mapping and factorial analysis (MCA), nodes, and dendrogram resulted Fig. 12 Thematic evolution of the author's keywords used during the study period in two time-slice zones (2004-16 and 2017-22) 1 3 in climate and climate change, water chemistry, weathering, glacier, and Antarctica/Arctic being the most significant keywords during the study period. The scientific productionbased analysis resulted that 2019 was the highest-producing year with 97 articles and 9.16% contribution, while 2002 and 2005 were the least contributing years of total publications. The USA and China were the most contributing countries, with 32.83% and 21.42% of the study. The highest index was  (22), followed by Geochimica Et Cosmochimica Acta (21). As per the types of documents published, the English language contributed the most, by 94.43%. England (43.67) and Norway (38.50) had the highest average citations, while the USA and China produced the highest total citations and publications. At the same time, the hydrochemistry and hydro-geochemistry of glacier meltwater are the emerging keywords. The content assessment has the limitation during the study as we had assessed only the web of science (WOS), which provides bibliometric data until July 2022. This study provides scientific exposure with qualitative values to the academicians, scholars, and scientific communities for a particular research field. It further provides scientific output to understand the global scenario of hydrochemical and hydrogeochemical research of meltwater at higher altitudes.