# Regional, national and international climate modeling

## Bioclimatic Parameter definitions

Bioclimatic Parameter definitions, taken from the ANUCLIM users manual

### 1. Annual mean temperature

• The mean of all the monthly mean temperatures. Each monthly mean temperature is the mean of that months's maximum and minimum temperature.

### 2. Mean diurnal range (Mean(period max-min))

• The mean of all the monthly diurnal temperature ranges. Each monthly diurnal range is the difference between that month's maximum and minimum temperature.

### 3. Isothermality 2/7

• The mean diurnal range (parameter 2) divided by the Annual Temperature Range (parameter 7).

### 4. Temperature seasonality (C of V)

• The temperature Coefficient of Variation (C of V) is the standard deviation of the monthly mean temperatures expressed as a percentage of the mean of those temperatures (i.e. the annual mean). For this calculation, the mean in degrees Kelvin is used. This avoids the possibility of having to divide by zero, but does mean that the values are usually quite small.

### 5. Max temperature of warmest period

• The highest temperature of any monthly maximum temperature.

### 6. Min temperature of coldest period

• The lowest temperature of any monthly minimum temperature.

### 7. Temperature annual range (5-6)

• The difference between the Max Temperature of Warmest Period and the Min Temperature of Coldest Period.

### 8. Mean temperature of wettest quarter

• The wettest quarter of the year is determined (to the nearest month), and the mean temperature of this period is calculated.

### 9. Mean temperature of driest quarter

• The driest quarter of the year is determined (to the nearest month), and the mean temperature of this period is calculated.

### 10. Mean temperature of warmest quarter

• The warmest quarter of the year is determined (to the nearest month), and the mean temperature of this period is calculated.

### 11. Mean temperature of coldest quarter

• The coldest quarter of the year is determined (to the nearest month), and the mean temperature of this period is calculated.

### 12. Annual precipitation

• The sum of all the monthly precipitation estimates.

### 13. Precipitation of wettest period

• The precipitation of the wettest month.

### 14. Precipitation of driest period

• The precipitation of the driest month.

### 15. Precipitation seasonality (C of V)

• The Coefficient of Variation (C of V) is the standard deviation of the monthly precipitation estimates expressed as a percentage of the mean of those estimates (i.e. the annual mean).

### 16. Precipitation of wettest quarter

• The wettest quarter of the year is determined (to the nearest month), and the total precipitation over this period is calculated.

### 17. Precipitation of driest quarter

• The driest quarter of the year is determined (to the nearest month), and the total precipitation over this period is calculated.

### 18. Precipitation of warmest quarter

• The warmest quarter of the year is determined (to the nearest month), and the total precipitation over this period is calculated.

### 19. Precipitation of coldest quarter

• The coldest quarter of the year is determined (to the nearest month), and the total precipitation over this period is calculated.

• On-going

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