approach benefits from:
Use of the same model for the nested suite means that treatment of the
dynamics and the parameterized/resolved physics processes are consistent.
s: A single model approach means that all runs in the suites benefit from model
science advances. In addition, to take advantage model development you only
need to re-run the UM nested suite, not necessarily your archived long term
climate simulations.
orography
Figure 1. Schematics of a) Met O
b) Nested domains orography
∆1km
The current approach is as described i
• Stage 1 UM nested suite runs for 2-m
∆333m
• The driving model is the Global NWP
• The nested model suite resolutions a
∆100m
• Both the driving model and the ∆12k
• Corrections are calculated with ∆4km
• Corrections are applied to archived c
Target sites are classified into 3 cate
model:
• Low complexity sites, (A/S) < 0.02
• High complexity sites, (A/S) ≥ 0.02
• Offshore sites
Orography (m)
ain orography [∆4km]
d) COLPEX domain orography [∆100m]
• Virtually all corrections based on the
better verifications than uncorrected
D
D
S
S
B
B
20km
X UM nested suite orography for a) ∆4km driving model, b) Nested model domains,
er target domain d) ∆100m model over target domain. With wind mast sites (D)
hill and (B) Burfield (no data for 15-day period).
∆1km
∆333m
∆100m
D
D
D
S
S
Simulations for 28 complex terrain lo
approach. Table 1 summarises the ve
should be viewed in relation to veri
processing, i.e. VMM, [0.870(0.985) m
• The best verifications statistics are
data with the ∆100m model data us
sectors to obtain the corrections.
Conventional thinking would imply th
data with highest resolution available
regression should yield better results
from Table 1, however, these results a
of sites which are loosely grouped
highly site specific as seen in the C
where the UM performed well for bot
∆100m resolution. In addition, the maj
UK, where the prevailing wind is south
In order to be able to make a more rob
verifications are required, ideally with a
S
At present, the Met Office is able to a