| Statistics on Desertification and Other climatic Variables |
Basic Statistics The supplied dataset (“Desertification”) consists of 1,1600 observations from 29 localities. Data are organized by monthly values of Wind, Temperature, Rainfall and Destert Storms occorrences per year (from 2003 to 2012). Herein, I will first reorder the data in to have them more handable, and then make four different dataframes, one for each of the four variables.
For each of the variable (Wind, Sandstorms, Rainfall and temperature) a barplot (with stabdard deviations) and a boxplot are produced. Moreover, by stations trends are visualized.
WIND
SANDSTORMS
TEMPERATURE
RAINFALL (there are some problems with this dataset, thus I will not
analyze it for the moment)
Finally, using a generalized mixed model, a prediction of future sandstorms is shown (Rainfall data not used for the moment)
## # A tibble: 29 × 9
## station Meansandstorms sd.x MeanWind sd.y Meantemperature sd.x.x
## <chr> <dbl> <dbl> <dbl> <dbl> <dbl> <dbl>
## 1 Abha 0.0818 0.335 6.27 1.22 28.3 3.76
## 2 Al-Ahsa 1.65 2.84 6.31 1.70 39.9 7.69
## 3 Al-Baha 0.118 0.631 6.19 1.66 32.9 6.45
## 4 Al-Jouf 0.7 1.40 7.55 1.24 34.6 7.99
## 5 Arar 0.327 0.743 8.05 1.41 35.4 8.87
## 6 Bisha 0.264 0.725 4.3 0.934 37.1 4.38
## 7 Dhahran 0.218 0.612 8.15 1.25 38.6 7.91
## 8 Dmmam 0.636 1.22 8.48 1.29 38.6 7.87
## 9 Guriat 0.373 0.876 8.43 2.20 33.6 8.08
## 10 Hafr Elbatten 1.06 1.88 7.67 1.61 37.5 8.25
## # ℹ 19 more rows
## # ℹ 2 more variables: Meanrainfall <dbl>, sd.y.y <dbl>
##
## Call:
## glm(formula = Meansandstorms ~ Meantemperature * MeanWind, family = "gaussian",
## data = Means)
##
## Deviance Residuals:
## Min 1Q Median 3Q Max
## -0.47930 -0.20708 -0.05359 0.13188 1.07398
##
## Coefficients:
## Estimate Std. Error t value Pr(>|t|)
## (Intercept) 0.83233 3.86797 0.215 0.831
## Meantemperature -0.02496 0.10126 -0.246 0.807
## MeanWind -0.35763 0.57746 -0.619 0.542
## Meantemperature:MeanWind 0.01189 0.01524 0.780 0.443
##
## (Dispersion parameter for gaussian family taken to be 0.1214393)
##
## Null deviance: 3.8667 on 27 degrees of freedom
## Residual deviance: 2.9145 on 24 degrees of freedom
## (1 osservazione eliminata a causa di un valore mancante)
## AIC: 26.111
##
## Number of Fisher Scoring iterations: 2
## Estimate Std. Error t value Pr(>|t|)
## (Intercept) 0.83232642 3.86797283 0.2151841 0.8314419
## Meantemperature -0.02495999 0.10126260 -0.2464877 0.8074008
## MeanWind -0.35762715 0.57746004 -0.6193106 0.5415467
## Meantemperature:MeanWind 0.01188954 0.01523875 0.7802178 0.4428901
## 1 2 3 4 5 6
## -0.004698916 0.571469628 0.220503262 0.372226468 0.457462622 0.265276653
## 7 8 9 10 11 12
## 0.697478574 0.730709562 0.350073987 0.573959619 0.371607604 0.567687077
## 13 14 15 16 17 18
## 0.347150853 0.094282250 0.466642488 0.122480965 0.232641338 0.495827243
## 19 20 21 23 24 25
## 0.483650842 0.477856397 0.435265856 0.496381530 0.638368255 0.258360064
## 26 27 28 29
## 0.270415513 0.168947963 0.368912622 0.641786953