Met Dept looks to radars to boost weather info

The radar is able to provide precise, area-specific forecasts of severe weather and climate occurrences, say experts. Extreme events such as tropical storms or hail can be accurately detected a day, even hours, before they occur or as they build up, they say.The Meteorological Services Department (MSD) is to put out a tender of $5,2 million for the purchase of five weather surveillance radars, as part of efforts to improve the provision of reliable weather and climate data, key tools to coping with climate change.

This comes as Agriculture Minister Perence Shiri on January 14 implored the MSD to issue out “long range forecasts” to help farmers, most of them reliant on periodic seasonal rain, plan better in the face of climate change.

Minister Shiri was speaking on the ZTV night news bulletin, commenting on this summer’s erratic rainfall patterns that risked producing false readings had the usual countrywide crop assessments come a few weeks earlier to the latest wet spell, when rain was scarce and crops badly damaged.

Now, the issue of radars isn’t particularly new. The Meteorological Services Department has for a long time pressured Government to release funds for their purchase. But the matter assumes a new significance with the impact that changing rainfall patterns, frequent and intense droughts and floods – all evidence of climate change – are having on Zimbabwe’s agri-intensive, and yet climate-sensitive economy.

Acting MSD director general Washington Zhakata said they filed tender documents with the State Procurement Board (SPB) for adjudication in December. But the papers have been held up because of the ongoing restructuring at the procurement body.

He expects to receive “the green light to buy the equipment” from the re-modeled Procurement Regulatory Authority of Zimbabwe, formerly SPB, soon. When that happens, the radars will be purchased in two separate batches, three at first and two later, at an estimated cost of $5,2 million in total.

“The tender documents have gone through. We await official communication from the Procurement Authority to proceed with the purchase,” Mr Zhakata told The Herald Business on January 15, by phone.

“Government is taking this issue (of radar acquisitions) very seriously.”

 The Herald Business understands that four of the five weather surveillance radars will replace those at Harare, Bulawayo, Victoria Falls and Buffalo Range in Chiredzi, which stopped working nearly 15 years ago after reaching the end of their 30-year lifespan.

Crucial  intervention
Zimbabwe’s climate scientists provide only limited rainfall data, and that is of little use to rural farmers, experts say.

Only a quarter of the country’s 1,400 weather stations are currently operational, due to neglect, amid a series of spending cuts at the State-run Meteorological Services Department since 2014. By September 2017 the MSD had received only a fifth of the $7,4 million it needed for current and capital expenditure.

Previously, weather stations placed in rural schools or clinics in the country’s drought-prone areas helped provide specific and accurate local data.

Today, the meteorological office tends to produce vague and generalised information for entire provinces, say Mashonaland Central, which consists of several large districts with differing climates. The surveillance radars are seen as key to bridging this gap.

“Weather radars’ particular importance has been its ability to detect and warn of hazards associated with severe local storms that include hail, high winds, and intense precipitation,” said Mr Zhakata, who doubles as director for climate change in the Ministry of Environment, Water and Climate, in a separate email.

 “Weather radars also improve aviation safety and increase the operational efficiency of the entire air transport industry, and they contribute to agriculture alerts and flood warnings through monitoring of rainfall intensity.”

Radar is short for Radio Detecting and Ranging, an object-detection system that uses radio waves to determine the range, altitude, direction, or speed of objects, according to the know-it-all online dictionary, Wikipedia.

Elisha Moyo, a climate change researcher with the Environment, Water and Climate Ministry, gave the clearest, practical benefit of weather radars.

“The weather radar has the ability to provide the precise location of a storm; its actual speed, its strength, its direction, its height and its characteristics. That enables us to predict accurately the time it will take, say a storm in Marondera moving at a particular speed, to reach Harare,” Moyo explained in a past interview.

“And you can actually see the speed of the winds within the storm. So, in terms of severity, we are able to detect violent storms better. At times we say there is a storm but we do not know how severe it is.

“With the weather radar, we are able to observe the storm with all its characteristics. The radar is very effective for monitoring and early warning (events building up at that specific time).”

However, the radar is weak on lead times, Moyo said. That is, it unable to provide data for precise predictions say a week or more ahead of the actual storm, flooding or heavy rain.

All the same, the radars would be useful for complementing the supercomputer that is stationed at the University of Zimbabwe, according to MSD head of forecasting Tich Zinyemba.

 “Depending on what variables you are looking at, with the High Performance Computer we get derived products, such as rainfall, temperature, wind regime at different levels of the atmosphere etc, which help us generate our weather forecasts.. Weather radars have different specifications, but they do complement the models we run with the HPC,” said Zinyemba, in a telephone interview.

Urgent recapitalisation

The Meteorological Services Department is severely incapacitated to effectively and efficiently perform its functions. Yet, the data and information it produces remains indispensable to policy and strategy formulation in face of dangerous climate change. Salaries are generally poor, sources say, leading to a high turnover of experienced and qualified staff.

In 2018, the Department was allocated $4,3 million, according to the 2018 Estimates of Expenditure from the Finance Ministry, but much of it will go towards staff costs and administrative expenses. It hopes Treasury will chip in on the radars purchase.

Some equipment at the MSD is now more than a 100 years old and no longer reliable. The earliest weather stations in Zimbabwe were set up at Harare and Bulawayo very early in the 20th century. The UK, a country almost half the size of Zimbabwe, has 15 weather radars dotted around the small island nation.

The four radars here catered for an entire country, although accuracy for areas outside the key radius of 200 to 400 kilometres receded. Mr Zhakata, the acting MSD director general, said the Department was “in urgent need of recapitalisa4ion”.

 “The Meteorological Services Department has been operating with very little capacity — human, equipment and financial — which compromises the quality of products and efficiency of the department as a whole,” he lamented, by email.

“This brings about the need for urgent recapitalisation of the MSD in terms of both human expertise, equipment for the observation network, financial resources for regular maintenance of equipment and transmission of vital data, among others,” he said without figures.

Makeshift rain gauge

In Uzumba, communal farmers are now looking to their home-made rain gauge to provide important rainfall data as scientific information from the MSD dries up.

About 30 other farmers from Zunzanyika village have compiled detailed records on local rainfall, learning to understand local trends and micro-climates and to cut the risk of crop failure.

The knowledge is helping them to cope not just with drastically changing rainfall patterns, but with limited local climate and weather data from the MSD.

 The makeshift but effective instruments consist of an old 500g metal or plastic jam container, secured firmly to the top of a tree stump or a wooden pole, 1 metre above the ground. Each of the 15 gauges in Zunzanyika is carefully stationed in an open space, away from obstacles.

The farmers use a classroom ruler to measure the amount of precipitation on the morning after any rainfall. The data is recorded on simple charts kept in their homes, and the information is shared among the field school members.

A farmer told this writer in a past interview that after four years of gathering data, he and his fellow farmers had a greater appreciation of when rains begin and end, how often dry spells occur and just how long the growing season lasts.

Source: The Herald

Post Author: Nyasha Nyakunu

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