Transport of Air Polutants to N. America

Preliminary calculations of a tracer transport during March 21 to 29, 1997. Horizontal grid spacing of 200 km. Results performed by Prof. Itsushi Uno , Kyushu University, using RAMS with on-line tracer, using strong nudging. Tracer is released continuously from a 3x3 grid area centered at E110 N40, and no wet removal is included. Tracer is released at 4 different levels surface, 1000m, 2000m 4000m.~10 time steps per day.


Figure 1. Shown as horizontal streamlines at 2 km and isosurface of surface released tracer (white) on March 25, 1997.


Figure 2. Same as Figure 1, but isosurface is tracer released at ~4km on March 25, 1997.


Figure 3. Same as Figure 1, but on March 29, 1997.


3/29/97 Figure 4. Birds' eye view. Same as Figure 3, but also shown are vertical velocity vectors along a curtain from China to Washington.


3/29/97 Figure 5. Same as Figure 4, but different viewing angle showing that the tracer is transported at ~5km height. The concentration of tracer along this curtain is shown in pink.