Less Green: NASA Finds Congo Rainforest Have Turned Brown due to Climate Change [VIDEO]

New NASA satellite data clearly shows that Africa's Congo rainforest has faced the brunt of climate change over the past decade, resulting in a drastic loss of green cover.

Analysis of the satellite data reveals that climate change has severely affected the second-largest tropical rainforest in the world- the Congo rainforest in Africa. In this analysis, the researchers considered greenness as a strong indicator of forest health. They noticed that capacity of the trees to photosynthesize has lowered significantly over the recent years.

Led by researcher Liming Zhou of the University at Albany, State University of New York, this study is one most of the comprehensive that investigates the effect of long term drought on the Congo rainforest using several independent satellite sensors.

"It's important to understand these changes because most climate models predict tropical forests may be under stress due to increasing severe water shortages in a warmer and drier 21st century climate," Zhou said in a statement.

In this study the researchers looked at the impact of drought on the rainforest since 2000. They noticed that between 2000- 2012, the forest region  faced degradation and decline and this gradually intensified. If this trend continues, the researchers fear that composition and structure of the Congo rainforest will undergo a massive change.

Till date the measurements of vegetation greenness was used to study the Amazon rainforest. But no study was done on the African rainforests that have less severe drought but long lasting ones  compared to the Amazon.

To study the impact of long term drought on Congo rainforest, they used the Enhanced Vegetation Index. This satellite measure was formed using data from the Moderate Resolution Imaging Spectroradiometer (MODIS) instrument on NASA's Terra satellite.

Analysis showed a gradual decline in the Congo rainforest greenness, which they refer to as 'browning'. This was  different from the impact witnessed in Amazon where there was largescale tree mortality due to more episodic drought.

The browning of the canopy observed was consistent with the decrease in the water available to plants.

"Combining measurements from different sensors has given us more confidence in the results of the MODIS data and provided us with insights into the environmental and physiological mechanisms of the browning observed by the MODIS data," said co-author Sassan Saatchi of JPL.

The other factors that pose an extra stress on plants are land surface temperature and decreased cloudiness.

"Forests of the Congo Basin are known to be resilient to moderate climate change because they have been exposed to dry conditions in the past few hundred years," Saatchi said. "However, the recent climate anomalies as a result of climate change and warming of the Atlantic Ocean have created severe droughts in the tropics, causing major impacts on forests."

This study helps understand how the African rainforests are responding to increasing drought. The finding was documented in the journal Nature.