The phrase "large deltas" refers to significant changes or differences between two things or situations. It signifies a considerable variation or gap between two points. Full definition
Raising the issue of long - term spending patterns versus tax receipts, he noted that very small gaps between the two, if they persist over an extended period of time, will create «some very large deltas.» (thinkadvisor.com)
A 2009 study found that 85 % of the world's largest deltas suffered severe flooding in the first decade of the twenty - first century. (scientificamerican.com)
The Nile, nearly 4,000 miles long, rises just north of the equator and flows northward to empty into the Mediterranean after forming a large delta on which is situated the important city of Alexandria. (religion-online.org)