Weather satellites take a picture of the entire world every 5 to 10 minutes. These images show cloud cover and the weather around you. They’re a great tool for meteorologists to use in short term weather forecasts.
Fire fighters rely on these weather satellite photos to monitor fires and when they will start to rain.
Temperature
The temperature in Chennai varies very significantly over the course of the year. This is caused by both climate and weather patterns. In the colder parts of the year, snow is common, and in the warmer parts of the year, temperatures are hot.
Satellite temperature measurements can help scientists track a range of weather events, including tropical cyclones, heat waves, and urban heat islands. They also allow researchers to monitor how Earth’s climate responds to changing greenhouse gas concentrations.
Temperatures in satellite imagery can be interpreted in many ways, but the most obvious is to determine how much heat the surface is absorbing from the atmosphere. This can be done by analyzing the infrared radiation emitted by atmospheric gases and water molecules.
Another important factor in understanding the temperature in chennai is to consider how it changes between day and night. Dew points are a key factor in this change, as they determine whether perspiration can evaporate from the skin and cool the body.
A lower dew point feels drier, while a higher one feels more humid. This perceived humidity is affected by the amount of cloud cover and can vary dramatically from one season to the next.
The climate in chennai is generally very pleasant, with little or no rainfall during most of the year. The peak travel season is from May to June, when temperatures are often very high and festivities are in full swing.
Rainfall
The Indian monsoon is one of the world’s most prominent systems, and India relies on it for about 70% of its rainfall, which helps feed the country’s agriculture and its citizens. It blows from the northeast during cooler months and reverses direction to blow from the southwest during the hottest summer.
As the monsoon moves closer to India, it brings heavy rainfall to the country, primarily during June and July. It also brings cyclones to the region, which are low pressure areas that form over warm water and then move eastwards and westwards as they move around a central point.
When cyclones hit the coast of Tamil Nadu, they can cause havoc in cities and towns, causing flooding, uprooting trees, and disrupting electricity supply. This is what happened to Chennai on December 9 and 10 as cyclone Mandous crossed the city’s coast near Mamallapuram, killing four people.
Besides uprooting trees, the cyclone also caused waterlogging in the city’s streets and drains. It also disrupted electricity supplies in many parts of the city, and forced the Greater Chennai Corporation (GCC) workers to clear roads for traffic.
It was a “freak event” that may not have been seen in the past century, climate scientists told The Wire Science. While they can’t explain the exact reason, they said that the heavy rains were likely a combination of several weather events that converged on a small area of the city.
According to climate scientists, the December 30 rains were a result of an interaction between an influx of moisture from the Bay of Bengal and an effect of the La Nina. The two events collided and caused the mighty torrent, which made its way into the city in an hour’s time.
But the IMD – India’s weather forecasting agency – was unable to predict the torrent, which was a “real freak event”. That’s because they use global models that have a limited amount of predictive power.
These models can’t determine the precise location of an impact, so the climatologists who run them have to make assumptions about the weather patterns and chemistry of the atmosphere. This can lead to inaccurate forecasts and even a failure to warn about an incoming event.
Wind
Weather satellites take a picture of the entire world every 5 to 10 minutes. Using these photos, meteorologists can determine the amount of rain that has fallen or is expected to fall. These maps can be animated to produce a minute-by-minute view of the weather, and are often used for short term weather forecasting.
Weather maps show a surface wind speed and direction (like a line across a map). The map itself is based on the pressure (weight per square area of air above) of the Earth’s surface at that time. The wind speed and direction can vary a lot between different locations, especially when there are wind shears – low or high pressure zones that change the direction of the wind.
Shears, in particular, can halve the local wind speed and alter its direction (always towards a low pressure). This is why it is important to look at the winds at higher altitudes rather than just at the surface.
The wind also affects the satellite signals that connect people to their homes. A weaker signal can cause the satellite to lose its connection to the ground, which could result in a loss of electricity, water, or communication services.
A stronger signal can make the satellite transmit the signal to a receiver, which will then convert that signal into radio waves. When the signal reaches a receiver, it can be used to make voice calls or send text messages.
Some weather satellites also carry a thermal imaging camera that takes pictures of the Earth’s atmosphere. These images are used to detect fires and to determine when it will rain.
There are a number of apps that allow you to track weather events from your phone or computer. One of the best is Weather Underground.
This app lets you see live radar from around the world, and offers future radar, which can predict storm movement up to six hours in advance. Its satellite map also lets you zoom down to street level.
The app also has a number of other features. It can help you determine what type of rain is falling, and it can show you the areas that are at risk of flooding.
Pressure
Pressure is a measure of force per unit area. It is commonly expressed in units of pascals (Pa), newtons per square meter (N/m2), or pounds per square inch (psi). Other units of pressure include atmospheres (atm), torr, bar, and millimeters of mercury.
The pressure that surrounds Earth’s surface is a combination of a large number of gases and the weight of the air above. At sea level, this pressure is 101325 Pa.
It is important for people to understand the pressure that is exerted on a surface because it can help them make better decisions about what they should do and where to go. For example, if you put a sharp pin in a bed of nails, the pressure on each nail tip will increase and it will be easier to hammer that nail.
If you put a blunt pin in the same bed of nails, however, the pressure on each of the pin tips will be lower because there is less surface area for the force to exert on. This means that it will be harder to hammer the blunt pin.
Because of the way that our bodies are built, we can’t exert as much force on a small surface as we can on a large one. This is why it’s so hard to lift something with a heavy weight. It’s the same reason that you can’t jack a car over very high bridges.
So, if you want to know what’s going on on a windy day, you need to be able to see the pressure at a higher altitude than the’surface charts’ that appear on TV or in newspapers. This is because the pressure at a higher altitude will be very different from the pressure at the surface.
To get this data, IMD telemetry teams use GPS sonde-attached balloons that are launched twice a day from the Meenambakkam observatory. They hover 35 km above the ground and drift around for about 60km, generating upper air pressure data that weather forecast models need to run.
These weather balloons can also be used to track a low-pressure system that could affect Chennai. But IMD officials say that their stock of GPS sonde-attached balloons is not sufficient enough to generate accurate upper air data for this purpose.