# CloudSat-inferred vertical structure of precipitation over the Antarctic continent

## TL;DR

This study uses CloudSat satellite data to analyze the vertical structure of Antarctic precipitation from 2007 to 2010, revealing regional and topographical variations and their implications for climate modeling.

## Contribution

It provides the first detailed analysis of Antarctic precipitation vertical structure using satellite data, highlighting regional differences and topography's role.

## Key findings

- High precipitation rates over peripheral regions with low seasonal variation.
- Low precipitation over the plateau with high seasonal variation.
- Precipitation distribution strongly depends on sea-ice coverage and topography.

## Abstract

Current global warming is causing significant changes in snowfall in polar regions, directly impacting the mass balance of the ice caps. The only water supply in Antarctica, precipitation, is poorly estimated from surface measurements. The onboard cloud-profiling radar of the CloudSat satellite provided the first real opportunity to estimate precipitation at continental scale. Based on CloudSat observations, we propose to explore the vertical structure of precipitation in Antarctica over the 2007-2010 period. A first division of this dataset following a topographical approach (continent versus peripheral regions, with a 2250m topographical criterion) shows a high precipitation rate (275mm/yr at 1200meters above ground level) with low relative seasonal variation (+/-11%) over the peripheral areas. Over the plateau, the precipitation rate is low (34mm/yr at 1200m.a.g.l.) with a much larger relative seasonal variation (+/-143%). A second study that follows a geographical division highlights the average vertical structure of precipitation and temperature depending on the regions and their interactions with topography. In particular, over ice-shelves, we see a strong dependence of the distribution of precipitation on the sea-ice coverage. Finally, the relationship between precipitation and temperature is analyzed and compared with a simple analytical relationship. This study highlights that precipitation is largely dependent on the advection of air masses along the topographic slopes with an average vertical wind of 0.02m/s. This provides new diagnostics to evaluate climate models with a three-dimensional approach of the atmospheric structure of precipitation.