The U.S. National Science Foundation (NSF) is offering a federal grant opportunity titled "Hydrologic Sciences (HS)" aimed at supporting research focused on continental water processes at various scales. Eligible applicants include non-profit organizations, independent museums, observatories, research laboratories, professional societies, and institutions of higher education located in the U.S., with a particular emphasis on projects that explore hydrologic processes, water interactions with environmental components, and responses to changes in land use and climate. The program has an estimated total funding of $12 million, with individual awards ranging from $30,000 to $1 million, and proposals are accepted on a rolling basis. For further information, applicants can contact NSF grants.gov support at grantsgovsupport@nsf.gov or visit the NSF publication at http://www.nsf.gov/publications/pub_summ.jsp?ods_key=nsf22540.