Cray Computer Corporation
Clock Speed: 
Dates Used: 
Tuesday, July 16, 1991 to Thursday, September 1, 1994
Microprocessor Peak Teraflops: 
Memory (terabytes): 
Number of Processors: 

The CRAY Y-MP2D/216 arrived at NCAR in June 1991. The machine was called "castle" after the 14,265-foot Castle Peak, following an NCAR tradition of naming computers for "fourteeners" in the Colorado Rockies.

The machine was the first supercomputer in North America dedicated totally to climate simulation. It was funded by the Model Evaluation Consortium for Climate Assessment (MECCA), a numerical laboratory hosted by SCD and devoted to modeling climate change due to greenhouse gases.

MECCA was sponsored by the University Consortium for Atmospheric Research (UCAR) and the Electric Power Research Institute (EPRI, the R&D arm of the U.S. electric utility industry), headquartered in Palo Alto, California, and. Other MECCA sponsors came from government, industry, and academia, representing U.S., Dutch, French, Italian, and Japanese interests.

Five days after castle came online, it was running at more than 90% capacity. For NCAR, the new Y-MP meant twice the computing power available for climate research. For scientists around the world, it meant getting model results in months instead of years.

Castle had two central processing units, 16 million 64-bit words of central memory, an integrated Solid-State Storage Device (SSD) with 128 megabytes of fast-access memory. It also had an Input/Output Subsystem (IOS), a separate computer which handled all the input and out put data and connected the Y-MP2D to Cray disk storage units, other computers, networks, and the Mass Storage System. Castle ran the UNICOS operating system.

Castle was funded by MECCA through December 1993.