Add time stepping naked planet model

Time-Stepping Naked Planet Model/Grading/Naked_Earth.py

@@ -0,0 +1,32 @@
+import matplotlib.pyplot as plt
+
+timeStep = 10           # years
+waterDepth = 4000        # meters
+L = 1350                 # Watts/m2
+albedo = 0.3
+epsilon = 1
+sigma = 5.67E-8          # W/m2 K4
+#nSteps = int(input(""))
+nSteps=200
+
+heat_cap=waterDepth*4.2E6 #J/Kg/deg
+time_list=[0]
+temperature_list=[400]
+heat_content=heat_cap*temperature_list[0]
+heat_in=L*(1-albedo)/4
+heat_out=0
+secs_in_yr=3.14E7
+
+for t in range(0,nSteps):
+    time_list.append(timeStep+time_list[-1])
+    heat_out=epsilon*sigma*pow(temperature_list[-1],4)
+    heat_content=heat_content+(heat_in-heat_out)*timeStep*secs_in_yr
+    temperature_list.append(heat_content/heat_cap)
+    heat_out = epsilon * sigma * pow(temperature_list[-1], 4)
+print(temperature_list[-1])
+#print(temperature_list[-1], heat_out)
+plt.plot(time_list, temperature_list, marker='.', color="k")
+plt.xlabel("Time (years)")
+plt.ylabel("Temperature (degrees Kelvin)")
+plt.show()
+