Agriculture Reference
In-Depth Information
Regions and Temperature Ranges of the HDD Climate Classification
Table A14.1
HDD Units
(°Celsius)
HDD Units
(°Fahrenheit)
Region
Qualitative Description
I
II
III
IV
V
944-1390
1391-1670
1671-1940
1941-2220
1700-2500
2501-3000
3001-3500
3501-4000
Very cool
Cool
Moderately cool
Warm
Very warm to hot
2220
4001
(CTL) is measured by the difference between the mean January and mean July
temperatures (for the southern hemisphere). The HDD system only roughly ac-
counts for the climatic factors that affect vine growth and grape ripening, but it
has been widely used to guide the expansion of grape production into cooler
areas in the New World.
Conversion Factors for SI Units (International System of Units)
and Non-SI Units, Including American Units
and SI Abbreviations
a
Used in This topic
Appendix 15
To Convert
Column 1 into
Column 2,
Column 1,
Column 2,
To Convert Column 2 into
Multiply by
SI Unit
non-SI Unit
Column 1, Multiply by
Length, area, and volume
3.28
meter, m
foot, ft
0.304
39.4
meter, m
inch, in
0.0254
3.94
10
2
millimeter, mm
inch, in
25.4
2.47
hectare, ha
acre, ac
0.405
0.265
liter, L
gallon
3.78
9.73
10
3
cubic meter, m
3
acre-inch, acre-in
102.8
8.11
10
4
cubic meter, m
3
acre-foot, acre-ft
1.233
10
3
35.3
cubic meter, m
3
cubic foot, ft
3
2.83
10
2
0.811
megaliter, ML
acre-foot, acre-ft
1.233
Mass
2.20
10
3
gram, g
pound, lb
454
2.205
kilogram, kg
pound, lb
0.454
1.102
tonne, t
ton (U.S), ton
0.907
Quantities per unit area
0.893
kilogram/hectare, kg/ha
pound/acre, lb/ac
1.12
0.446
tonnes/hectare, t/ha
tons (U.S.)/ac, ton/ac
2.24
0.107
liter/hectare, L/ha
gallon/ac
9.35
