The University of Arizona has once again been recognized as the world's No. 1 program in water resources by the Shanghai Academic Ranking of World Universities, which released its 2019 rankings of academic subjects on Wednesday.

The UA earned the top spot in water resources in 2018, as well.

"I am proud to see that the cutting-edge water resources research conducted by University of Arizona scientists is recognized once again with this ranking,” said UA President Robert C. Robbins. "Water is our most precious natural resource, and our global leadership in this area has far-reaching and intergenerational impact."

The Shanghai ARWU subject rankings score more than 1,200 global universities based on the number of papers authored by an institution in an academic subject, the ratio of citation of papers published to the average citations of papers in the same category, the number of papers published in top journals, the amount of international collaboration and the total number of staff members that have won significant awards.

The UA's total score for water resources – 288.4 – put it ahead of the Swiss Federal Institute of Technology Zurich, the Beijing Normal University, the Delft University of Technology in the Netherlands, Texas A&M University and Hohai University in China. The UA ranked No. 3 in this program in Shanghai's inaugural subject rankings in 2017.

The UA also earned high marks in library and information sciences (No. 10) and communication (No. 15).

In other subjects, the UA tallied top-50 rankings in ecology (No. 17), earth sciences (No. 29), geography (No. 29), education (No. 44) and aerospace engineering (No. 48).

Shanghai ARWU ranks 54 programs in five categories – natural sciences, engineering, life sciences, medical sciences and social sciences.

The ARWU's institutional ranking was first published in June 2003 by the Center for World-Class Universities, Graduate School of Education (formerly the Institute of Higher Education) of Shanghai Jiao Tong University, China, and has been updated on an annual basis. Since 2009, the ARWU has been published and copyrighted by ShanghaiRanking Consultancy.