Action Items

Sedona, Arizona
27 - 29 January 2004

1. A benchmark statistical description of the sub-grid scale velocity field is needed. - R. Brown, R. Frehlich, D. Emmitt, R. Foster

2. Prepare a proposal to support a targeted observations field experiment with a wind lidar on a C130 or other aircraft. - M. Hardesty, Z. Toth, E. Kalnay

3. Prepare a whitepaper comparing a lidar and other wind sensors. M. Kavaya, P. Flamant, I. Guch

4. Develop a proposal for deployment of a wind lidar on commercial aircraft. - R. Fleming, R. Atlas, D. Emmitt, M. Hardesty

5. A co-plot of the CTI CAMEX backscatter data and the recent GTWS 2 micron backscatter profiles is needed. - P. Gatt, D. Emmitt

6. Is a space-based DWL the appropriate technology solution for global tropospheric wind profiles? - D. Emmitt, R. Atlas, J. Yoe to prepare the answer

The requirement for global coverage can be satisfied only using a satellite-based wind sensor or sensor suite. The requirement for profiles makes Doppler lidar the appropriate wind sensor to deploy on satellites.

This is illustrated by the table below, in which the rows correspond to required wind measurement characteristics, and the columns to wind sensors and platforms. Each cell is marked Y (yes) or N (no) to indicate whether a sensor can satisfy a given requirement. Space-based Doppler wind lidar is the only sensor category that offers the possibility of satisfying all of the requirements.

SENSOR/METHOD

DWL

SCT

CTW

ACARS

RS

WP

SB/AC

AC

Required Feature

DRL

DS

DRL

Global Coverage

Y

Y1

Y

N

N

N

N

N

Vertical Coverage

Y

N

N

N1

Y

Y

Y

Y

Vertical Resolution

Y

N

N

Y2

Y

Y

Y

Y

Horizontal Resolution

Y

Y

Y

Y

Y

N

Y

Y

Accuracy & Precision

Y

Y

N

Y

Y

Y

Y

Y

All Weather

Y3

Y

Y

Y

Y

Y

Y

Y

Frequency of Obs

Y

Y

Y

Y

Y

Y

N

Y

Feasible for Ops

Y

Y

Y

Y

Y

Y

N

N

Key:
DWL = Space-based Doppler Wind Lidar
SCT = Space-based microwave scatterometers for ocean surface winds
CTW = Cloud Track Winds inferred from a number of satellite imagers at various wavelengths
ACARS = in situ wind sensors deployed on commercial aircraft
RS = Radiosonde (weather balloons)
SB/AC = High altitude vehicles (balloons or planes) releasing dropsondes
WP = ground-based (Doppler) wind profilers, usually radar but possibly lidar
AC = Aircraft equipped with Doppler radar or lidar
Y1 = Excluding over land
Y2 = in the vicinity of airports, however
Y3 = Except below thick unbroken clouds
N1 = Except in the vicinity of airports

Why are global wind profiles necessary? (I added this question, since Dave Emmitt/Ingrid Guch have already provided a clear answer to it, and it gives clear context for the questions addressed in AIs 7,8,9 -Jim Yoe)

Analytic and numerical studies conducted during recent decades consistently indicate that additional wind data have far greater marginal information content - and hence potential to improve weather forecasting - than additional mass field (temperature and moisture) observations. The most complete set of added information is represented by accurate wind profiles (winds taken at many heights throughout the depth of the troposphere) over the entire Earth.

7. How do we interpret multiple OSSE results? - J. Yoe, R. Atlas, D. Emmitt

Although the magnitude of the predicted impacts and even the choice of impact metrics vary considerably, all of the recent OSSEs performed at NOAA and NASA using current global and regional forecasting models show significant positive impacts from plausible DWL concepts. The varying results are essentially a result of the different techniques used in simulating existing and proposed observing systems and in assimilating the simulated data products.

8. How do we ensure the NWP centers are ready to use wind profiles when they become available? - D. Emmitt, J. Yoe, W. Baker

The OSSEs are not only useful for establishing data requirements and evaluating DWL instrument/mission concepts. Completion of a wind OSSE requires that the algorithms, techniques, codes, and experience for assimilating real, high quality wind observations be prepared well before the launch of the instrument that will deliver them.

To promote a successful and expedient transition to operations, it is important to support and sustain the OSSE efforts in environments closely linked to the operational NWP centers. To ensure that sufficient resources are devoted to making the transition to operations, directors of the NWP centers must be informed of the expected value of the data and of mission prospects and schedules.

9. DWL FAQs should be sent to I. Guch for posting on the website. - All

10. Reconvene an Executive Steering Committee to advise NASA/NOAA on actions required to implement the wind lidar roadmap. - I. Guch, S. Neeck

11. The Lidar Working Group should use the Lidar Technology Roadmap to track progress and provide updates to Ken Miller.

12. The science requirements should be posted on the website. - J. Yoe

13. The use of GLAS data to improve the height assignment of GOES winds should be pursued. - J. Reagan