"The maize used to grow as tall as this," Chipuriro said measuring the length of his fore-arm. "But now, it only grows to a palm's length. It is useless."

He said that the yields are so low that he can no longer feed his wives and more than 10 children. "There is nothing to farm so I come out for work, otherwise my family will be starving."

Across the country, the output of maize, the staple food for Zimbabweans, is on the decline. The UN World Food Program estimated that up to 1.6 million Zimbabweans require aid this year.

A research conducted by SARDC in 2010 pointed out that the agricultural sector is a critical mainstay of local livelihoods and national gross domestic product for the eight countries around the Zambezi basin, the fourth largest river basin in Africa.

In Zambia, drought-induced crop failures have been the most common disasters experienced in the recent past. Crop failure due to increased severity of floods has also affected Mozambique, the report said.

Tomaz Salomao, executive secretary of Southern African Development Community, said the issue of climate change in southern Africa region is very critical, rendering available water resources in the Zambezi river basin to be stressed as a result of overall changes in the timing and extent of precipitation.

Environmental experts said though Africa is a small contributor to greenhouse gases, millions of impoverished rural Africans bear the brunt of the disastrous climate change impacts as they depend so much on rain-fed agriculture.

Other than food security, farming has been a pillar of income for rural Zimbabweans. According to the SARDC report, agriculture employs around 70 to 80 percent of the total labor force in the eight Zambezi river basin countries.

In Zimbabwe, where urban jobs have shrunk over the past decade, life becomes increasingly difficult for unskilled rural poor.

"Many people in my hometown are willing to come out, but they only know farming," Chipuriro said. "There is few jobs for them in Harare and they will have no place to stay."

The impact of climate change in Zimbabwe is so severe that it warrants the attention of President Robert Mugabe in his speech to mark the country's 33 rd independence anniversary.

"Fellow compatriots, we now know the story of climate change only too well. Once again, this year, the early rains promised a good agricultural season only for us later to face the stress of a prolonged mid-season dry spell in most parts of the country," the veteran leader said the persistent droughts are "clearly a result of climate change."

Mugabe told a crowd of 60,000 gathering at the National Sports Stadium on March 18 that as the government closely monitors the situation, drought mitigating measures have been adopted which include a national irrigation policy.

But experts say though irritation is an effective means of mitigating climate change, there is still a long way to go for Zimbabwe as the implementation of the irrigation policy requires a sustained and reliable funding source, which the cash-strapped government will be struggling to provide.