Simulation of errors for the nadir altimeter

Two main components of the nadir altimetry error budget are simulated : the altimeter noise and residual wet tropospheric errors. For the altimeter noise, the noise follows a spectrum of error consistent with global estimates from the Jason-2 altimeter. The wet tropospheric residual errors are generated using the simulated wet tropospheric signal and radiometer beam convolution described above for the KaRIN data.