AR Location issue

I'm using GPS values to make an object exist in a certain Lat Lng. To put it into Unity coordinates, I'm using this function:

Code (CSharp):

1. /// <param name="lat">Latitude</param>
2.     /// <param name="lon">Longitude</param>
3.     /// <param name="h">height.</param>
4.     Vector3 WGS84ToCartesian(float lat, float lon, float h)
5.     {              
6.         float cosLat = Mathf.Cos(lat * Mathf.PI / 180.0f);
7.         float sinLat = Mathf.Sin(lat * Mathf.PI / 180.0f);
8.         float cosLon = Mathf.Cos(lon * Mathf.PI / 180.0f);
9.         float sinLon = Mathf.Sin(lon * Mathf.PI / 180.0f);
10.  
11.         float f = 1.0f / 298.257224f;
12.         float C = 1.0f / Mathf.Sqrt(cosLat * cosLat + (1 - f) * (1 - f) * sinLat * sinLat);
13.         float S = (1.0f - f) * (1.0f - f) * C;
14.         float earthRadius = 6378137.0f;
15.  
16.         float x = (earthRadius * C + h) * cosLat * cosLon;
17.         float y = (earthRadius * C + h) * cosLat * sinLon;
18.         float z = (earthRadius * S + h) * sinLat;
19.  
20.         return new Vector3 (x, y, z);
21.     }
22. }

The problem is, it seems to be almost at a rotation. When I move away from the object, rather than seeming to move backward in the z direction, it seems to go up in the y as well, making it climb into the sky. Is this because of the curvature of the earth? Btw, I'm also using altitude for height.