**Group 2. Lagrangian dynamics (Lenschow) **

Analysis of the balloon trajectories, including estimates of divergence and synoptic conditions during the Lagrangian, is being carried out and will be written up by Businger and collaborators.

Analysis of the C-130 aircraft data for Lagrangians A and B is being carried out and will be written up by Wang and collaborators. This will include estimates of net entrainment rates by both the mean divergence and the flux profile techniques. The flux profile estimates will be based on humidity and ozone fluxes obtained from the circle flight paths. Boundary-layer turbulence variables will be analyzed and plotted, and analysis of coherent structures that are important for transport will also be conducted.

A more detailed analysis of entrainment in Lagrangian B will be carried out and written up by Russell and collaborators. This analysis will include the separation of the lower part of the troposphere into two layers, and entrainment across the interface between these two layers in both directions. These separate entrainments rates are estimated by use of dimethyl sulfide and aerosols in the 10 to 30 nanometer size range, and compared with estimates from analysis of turbulence data.

A documentation of the mean divergence technique for estimating entrainment rate will be carried out by Lenschow and collaborators. This will include analysis of the accuracy of the technique and discussion of examples that illustrate its application.

Remaining issues to be considered are how to obtain estimates of the height of inversion layers from the lidar data for: (1) Lagrangian A and (2) the remaining flights which contain circular flight patterns. Krista Laursen (NCAR/RAF) did this for Lagrangian B. At this point we do not know whether she is available and willing to do this also for Lagrangian A and for the rest of the flights. We recommend that if she is not willing or able to carryout this analysis, the JOSS be asked to carry it out. This analysis is necessary in order to estimate entrainment rates from the mean divergence technique. Paul Krummel (CSIRO, Australia) has already carried out the analysis of the mean divergence measurements from the circles. At this time, no one is committed to carry out calculations of entrainment rates from the flux profiles for flights other than Lagrangian A and B. This means that there is currently no paper planned that will provide estimates of entrainment for these flights.