Our historical records indicate 400C as the highest recorded temperature in Sri Lanka
Last year the maximum and highest recorded temperature was close to 38.60C.
the wind pattern and the ocean currents strive to create an energy balance resulting in the changing weather conditions
rain is often another output of the energy balance created by nature
With the weather becoming uncomfortable and hot during day time and cool during the evening hours, it is challenging to decipher the accuracy of a seemingly unpredictable weather. In a candid interview with Dailymirror , Director of Forecasting of the Department of Meteorology, Anusha Warnasuriya explained the intricacies of the weather pattern currently experienced in the country while Consultant Physician at the Colombo South Teaching Hospital and the President of the Sri Lanka Geriatric Association Dr. Dilhar Samaraweera advised citizens on how to be safeguarded against the risk of suffering a heatstroke when the temperature rises.
Prevalence of hot weather
Stating that the current hot weather prevailing in the country especially during the day time is by no means a heat wave, but a warm weather condition, Warnasuriya clarified that a heat wave is the prevalence of hot weather for two or three consecutive days, where an increase of 50C - 60C above the average temperature is recorded. She further noted that there are varied definitions available to explain a heatwave. “At present the temperature is a little bit warmer. This is because normally March, April and May are warm during the year. The main reason for the prevailing warm weather is the absence of significant wind speed over the country. The second reason is the high humidity level in the country. Since this is the inter monsoon period, the weather condition during morning hours tends to be very sunny and the sun rays are received by the earth thereby creating a warm weather condition. These three factors contribute to the warm weather condition currently experienced in the country” she said.
The main reason leading to this discomfort and the feeling of warmth is perspiration. The sweat we perspire has no means of evaporating due to the lack of wind and the saturated humidity in the surrounding environment
“It should be noted that this warm condition is by no means the maximum temperature. We have prepared a heat index using the maximum temperature and humidity level. This is sometimes recorded as 500C or 400C, which people tend to falsely take into account as the maximum temperature. However, this is not the maximum ambient temperature, but is only an index. This index is actually indicative of what we feel; in the present case it is a little bit uncomfortable and warm. The main reason leading to this discomfort and the feeling of warmth is perspiration. The sweat we perspire has no means of evaporating due to the lack of wind and the saturated humidity in the surrounding environment,” Warnasuriya said.
Elucidating that Sri Lanka is a small country surrounded by a vast oceanic area, Warnasuriya said that the islanders don’t experience very high temperatures. “Our historical records indicate 400C as the highest recorded temperature in Sri Lanka, which was a few decades ago. Last year the maximum and highest recorded temperature was close to 38.60C. So far we have recorded a maximum temperature of 360C for this year. The effect of the heat is less in Sri Lanka compared to India. This is because India has a much bigger land mass thus attracting more heat through the rays of the sun. Generally, when there is an upper level of wind or if there is any mechanism to get the wind flow upward, the heat condition might cease. But in India, there is a high pressure cell resulting in trapping this air mass. This is one reason for the very warm condition experienced in India at present. However, this is not the case in Sri Lanka” she added. According to Warnasuriya during this time of the year, the seasonal high pressure cell is over India and not over Sri Lanka. Compared to India and Pakistan, Sri Lanka is not much in danger of being exposed to the threat of a heat wave because it is a small landscape surrounded by an ocean with a considerable wind flow.
The Department of Meteorology with the assistance of the Ministry of Health, issued a recent bulletin on precautionary measures to be taken during the warm weather. Instructions were given to increase the intake of liquids while avoiding exposure to hot sun as much as possible
Nevertheless, the Director warned people to take precautions against the warm temperature experienced in several parts of the country since it may adversely affect the health of people, especially young children, infants and the elderly including individuals who are working outdoors and exposed to the sun for long hours. The Department of Meteorology with the assistance of the Ministry of Health, issued a recent bulletin on precautionary measures to be taken during the warm weather. Instructions were given to increase the intake of liquids while avoiding exposure to hot sun as much as possible.
If the patient is suffering from heat and exhaustion, immediate measures should be taken to cool himself either by pouring water on the body or if possible, it is much better to immerse himself in water
Explaining the reason behind the unpredictable weather pattern where showers may occur in several places whilst it is bright and sunny in other parts of the land, Director Warnasuriya briefed that this is a result of nature attempting to strike an energy balance in the environment. “The energy balance is facilitated by the wind patterns and the ocean currents. Hence, the wind pattern and the ocean currents strive to create an energy balance resulting in the changing weather conditions experienced across the country. If this energy is not balanced, our equatorial ocean temperature would be around 1000C” she said.
“This year, the average date for the South - West Monsoon is May 26 in Sri Lanka. There should be at least a pressure gradient of 2.5 across Sri Lanka with rains in Colombo, Galle and Ratnapura for at least three consecutive days, in order to declare it as the commencement of the South - West Monsoon. It is expected that the south -west monsoon would arrive in Kerala in India on June 1. However, it has been reported that they expect the rain a little earlier than on June 1. Therefore, we also expect that the South -West Monsoon might start a little earlier in Sri Lanka (particularly between May 20- 28). The onset of the monsoon is a very critical period for Sri Lanka especially between the last week of May and the first week of June. After the critical period concludes, we can expect rain settling in as a spell of showers in the country” Warnasuriya concluded.
According to Warnasuriya, in April and August the sun will be overhead twice per year. But people are more familiar with relating to this phenomenon during the April season and not during August. “This is mainly because we have a very good wind pattern flow during August compared to April. On the other hand, it must be noted that rain is often another output of the energy balance created by nature. These are the reasons why it is sometimes difficult to predict the weather very accurately and this is why we have a weather forecast instead” Warnasuriya explained.
Heatstroke and what you need to know
Speaking to Daily Mirror, Dr. Samaraweera explained that heatstroke is a condition in which the body temperature could rise above 1040F / 400C or higher leading to the loss of function or loss of consciousness eventually. Explaining that a heatstroke is often followed by sever dehydration, Dr. Samaraweera said that the patient would fail to maintain the normal body temperature under such conditions. He further explained that the human body has a mechanism of producing much sweat and evaporating it to maintain the normal body temperature. However, when a person is dehydrated, his or her ability to sweat will entirely stop thus increasing the patient’s body temperature. “This will result in the condition known as ‘Cutaneous Vasodilation’ where the body will try to maintain the temperature by diverting the blood to the skin. This helps in reducing body heat. The blood vessels will dilate in the skin causing sweat, thereby lowering the body temperature and bringing it to the normal rate. This process will try to maintain a constant blood supply to the skin albeit under such circumstances the blood supply to the brain will be compromised. Hence, when this happens, one may have alteration of the level of consciousness or may experience total loss of consciousness and even result in death. This is heat stroke explained in a nutshell,” Dr. Samarwaeera said.
According to the doctor, symptoms of a heatstroke may include a low rate of sweating accompanied by muscle cramps, weakness of muscles, exhaustion and a very red and bright coloured skin tone. Increased heart rate accompanied with rapid and shallow breathing, feeling faint, vertigo and headache are among the other symptoms of a heatstroke. This will eventually be followed by the loss or alteration of consciousness.
“When a patient experiences any of the symptoms related to a heatstroke, it is vital that the patient should immediately rest and seek a place that offers shade. If the patient is suffering from heat and exhaustion, immediate measures should be taken to cool himself either by pouring water on the body or if possible, it is much better to immerse himself in water, in order to bring down the temperature. Sponging or cold compressing the body using cold water and fanning is also advisable” Dr. Samaraweera said.
“Oral Rehydration Solution (ORS) is ideal to be administered to a patient affected by a heatstroke since it also contains salt. Also, king coconut which is the closest replica to saline is a much better natural solution that could be provided to a patient suffering from heat stroke” he said.
Elucidating further on the preventive measures that could be employed against the risk of a heatstroke, Dr. Samaraweera advised not to leave anyone and especially children locked inside a vehicle parked under the sun since the temperature inside a parked vehicle left under hot sun could rise by 200 F or more than 6.70C within ten minutes. He also advised that in average, people need to consume at least eight glasses of water or liquid intake for a day which is the equivalent of approximately two litres. In the case of extreme hot weather conditions, the intake of water or liquids can be increased up to twelve glasses. Advising against the exposure to sunlight between 11.00 a.m. and 3.00 p.m. when the heat would be extreme, Dr. Samaraweera cautioned against engaging in strenuous activities when the temperature is high since it could result in exhaustion. The doctor further advised to wear light and comfort clothing instead of opting for bulky and dark clothes as a preventive measures against heatstroke. Wearing sunscreen and ensuring the facilitation of proper ventilation in buildings for those living indoors were also recommended by Dr. Samaraweera during the hot weather.
Pix by Waruna Wanniarachchi