ime Required:
Contrails/chemtrails can be observed, photographed and reported in only a few minutes a day.
Scientific studies of contrails take more time and can provide important scientific information.

Contrails can spread into cirrus clouds that reduce sunlight during the day, thus causing a cooling effect. But contrails also trap heat during both the day and the night. It is not yet certain if the net result of these effects warms or cools the Earth, but most studies indicate that contrails have a net warming effect on our planet.

Scientists at NASA’s Langley Research Center in Hampton, Virginia found that the increase in temperature over the United States from 1975 to 1994 closely matched the increase expected from the presence of contrails. Dr. Patrick Minnis is a senior research scientist at the Langley Research Center. He has measured a one percent per decade increase in cirrus cloud cover over the United States, which is likely due to contrails. Minnis estimates that cirrus clouds from contrails increased the temperatures of the lower atmosphere by anywhere from 0.36 to 0.54 degrees F per decade. Minnis’s results show good agreement with weather service data, which reveal that the temperature of the surface and lower atmosphere rose by almost 0.5 degrees F per decade between 1975 and 1994. Reference.

An unprecedented opportunity to study the effect of contrails occurred during the 3 days following the terrorist attacks in New York and Washington on 11 September 2001. David Travis of the University of Wisconsin, Whitewater, found that during the virtual absence of contrails the difference in the high and low temperatures each day increased 1.1 degrees Celsius (2 degrees Fahrenheit) on each day. Reference.

The significance of all this is not fully established–which is where you come in. Observations and measurements of cirrus clouds by students, citizen scientists and weather observers might lead to new insights and discoveries that will be of serious interest to the professional scientists who study the impact of contrails on weather and climate. Significance:
Contrails are often more difficult for satellites to detect than clouds, especially when they remain narrow and do not spread outward. Students, home weather station operators and citizen scientists can provide important scientific information by documenting the contrails they observe and reporting their findings. It is important simply to know the number of days contrails were present over a particular location in a given year.
Project Links:
Contrail Education
SCOOL: Observing Contrails
SCOOL Cloud Chart: Contrails
GLOBE Contrail Gallery
GLOBE Contrail Resources
Real Time Data Source:

MODIS provides the best resolution satellite imagery that is freely available in near real-time through the MODIS Rapid Response System. Use the highest resolution images to look for contrails. MY NASA DATA Source:

Because contrails are hard to detect in current satellite imagery, there is currently no standard source. A related parameter of interest in the LAS is Atmosphere, Clouds, Cloud Coverage, Monthly Cloud Coverage for Cirrus (ISCCP). Also Monthly Cloud Coverage for Cirrostratus (ISCCP) or Monthly High Cloud Coverage (ISCCP). Some of the clouds detected in these categories may in fact be contrails, or of contrail origin. The presence of high clouds also indicates possibly more favorable conditions for contrails to occur. Project Ideas:
 We show that the radiative forcing associated with contrail cirrus as a whole is about nine times larger than that from line-shaped contrails alone

Serious students, citizen scientists and weather watchers in areas where persistent contrails are common can measure their effect on local temperature. This is best done by automatic home weather stations or data loggers that store temperature at preset or programmable intervals. You will need to devise a way of recording the presence of contrails at the Sun to make sense of the temperature data. A digital camera is ideal for this purpose. Even an inexpensive camera can be used.
Get a lumen meter and a UV meter plus a thermometer and measure the difference under a contrail-cirrus sky and under a cloudless sky

1. Daily Contrail Observations. You can easily add contrail watching to a regular program of cloud observations (see Science Project 2: Cloud Studies, Science Project 1: Clouds for Kids). When contrails are visible, describe them as (1) short and transient, (2) long and persistent or (3) spreading. Be sure to note if cirrus clouds are present.
1) I call chemhaze 2) I call chemtrails 3) I call and scientists too contrail-cirrus. "Be sure to note if cirrus clouds are present" man-made or natural? 

2. Special Contrail Observations. Spreading contrails have much more impact on sunlight and heat retention than other contrails. When you see spreading contrails, describe their coverage of the sky in terms of oktas (seeScience Project 2: Cloud Studies, Project Idea 2).
 We show that the radiative forcing associated with contrail cirrus as a whole is about nine times larger than that from line-shaped contrails alone

3. Contrail Photographs. Contrail observations can be combined with sky photographs to provide a dynamic record of the presence and appearance of contrails. There simply is no better way to study contrails. Photography is an especially good method for recording spreading contrails and clusters of intersecting and parallel contrails.
Not enough. You need the upper atmospheric data too and should record the data of planes flying - Live flight tracker!   under old chemtrails or contrail-cirrus. That way you know their altitude and by checking the atmospheric sounding of the nearest sounding station you will far to often find out that those "cirrus" clouds are at a far higher and dryer altitude and should actually not exist. Atmospheric Soundings

4. Contrails and Satellite Images. Contrails are clearly visible in some satellite images. For example, this photograph from the International Space Station shows both narrow and spreading contrails over France south of Geneva, Switzerland. Far more contrails are visible in the image from NASA’s Terra satellite. Comparing your ground reports and photographs of contrails with satellite imagery over your location would make for a fascinating science project.
I did something similar. See how a chemtrail goes allover North Africa tracking/WV-Captures/index.html

5. Contrails and Airports. On days when the atmosphere allows contrails to form, contrails are not produced until aircraft taking off from airports reach a certain altitude, usually above 7.5 km (24,600 feet) or higher. On some days cities with busy airports will be overlain by high contrails from planes passing by and surrounded by contrails produced by aircraft leaving and arriving at the airport. With perfect conditions and a clear sky, the airport might appear as if at the center of a wheel with radiating white spokes extending outward. If you live in the general vicinity of but not too close to a large airport, you can observe, record and photograph contrails related to the jet traffic at the airport.
It's not altitude dependent but temperature dependent. I consider this now disinformation. For contrails to form it has to be at least -38C or colder. He should know that. I lived near the airport of Athens and I live now near an airport but never had radiating white spokes extending outward  We had it as a game in my childhood to look out for contrails over Athens and not one time did we saw a contrail without an airplane or contrails lasting longer than about half minute or super long contrails going from one end of the sky to the other end of the sky. ....

6. Contrails and Weather. Why are contrails not visible all the time? The reason is that contrails form only when the temperature of the air is at or below -40 degrees Celsius (-40 degrees Fahrenheit) and the relative humidity is sufficiently high. So the presence of contrails high overhead provides clues about the temperature up there. Are contrails related to local weather? A good science project would involve comparing local weather patterns on days when contrails are and are not present.
Well, the relative humidity part is new to me for contrails or is he deliberately  mixing up info about contrails with "persistent-contrails" because debunkers do this too. Putting contrails, persistent-contrails and contrail-cirrus in one pot and naming them all "contrails" while refusing to call contrail-cirrus, contrail-cirrus and just call them "cirrus" as to suggest those were natural. Remember this:
 We show that the radiative forcing associated with contrail cirrus as a whole is about nine times larger than that from line-shaped contrails alone. A good science project would involve comparing local weather patterns on days when contrails are and are not present. Disinformation again because contrails are every day present but he is now probably talking about "persistent-contrails" or have you noticed a single day in our days with no contrails? By the way: I don't remember seeing ANY contrails over the Greek islands from 75 to 83 when I spend 6 entire Summers on the Greek islands. So I think contrails are most likely related to pollutants.

7. Contrails and the Seasons. In some regions contrails occur throughout the year. In other areas they may tend to occur more during cooler months. What is the significance of this? Study the seasonal prevalence of contrails in your area to find out. Compare the presence of contrails with the temperature and other weather patterns. You may wish to explore the Appleman Chart activity to help understand this.
I see contrails every day if the sky is not covered by low altitude clouds. Since this report is old it suggests that in the past contrails were not seen every month. Strange.....

8. Contrails and Humidity. Water vapor in the atmosphere is commonly expressed in terms of the relative humidity, a measure of how much water vapor is present to the maximum amount the air can hold at a particular temperature. Warm air can contain far more water vapor than cool air, so ‘relative humidity’ does not represent the actual amount of water vapor in the air, but a relative measure of how much water vapor it could hold. In order for a contrail to form, the relative humidity must be very high at the aircraft altitude. Is this related to relative humidity near the ground? Collect data on relative humidity and contrail occurrence for at least 10 contrail days, and you will have the makings of a first class science project.
He is talking now again about "persistent-contrails" aka chemtrails. Collect data on relative humidity and contrail occurrence for at least 10 contrail days, Just do this and tell us if there was a single day ( when there was no cloud cover ) you didn't see contrails.

9. Contrails and Temperature. When spreading contrails block the sun, they can cause a temporary and measurable reduction in the temperature at the ground. The best way to study this is by means of a digital thermometer that automatically measures the temperature throughout the day at periodic intervals. The GLOBE program has several temperature protocols from which you can select. Some of these use commercial digital electronic weather stations made by Davis Instruments and Weather Hawk. The Onset Computer Corporation makes moderately priced, miniature temperature data loggers that are ideal for this project. Their Pendant loggers are especially good. No matter which instrument you select, it is important that the thermometer be kept from direct sunlight as described in the GLOBE protocols.
Chemtrails are only slightly cool the temperature during midday but later when Earth is suppose to cool down it doesnt happen because chemtrails are like a blanket. Most radiation comes in but the resulting infra red radiation is trapped under the chemtrail blanket. When spreading contrails block the sun Why is he using the word spreading all of a sudden?

10. Contrails and Sunlight. Contrails often block sunlight more effectively than ordinary cirrus clouds at the same altitude. As with temperature, the best way to measure this effect is to use an automatic instrument that records sunlight. The Onset Computer Corporation makes moderately priced, miniature light recording data loggers that are ideal for this project. An ideal choice is one of their light-sensing Pendant models. Note that it is necessary to place the light sensing data logger in full sunlight in order to measure the effect of contrails. Data loggers such as the Pendant record both temperature and light, and the temperature will be reduced when a contrail blocks the sun. But the direct sunlight temperature measurement will be higher than the air temperature in the shade. So, if you want to measure the impact of contrails on both light and temperature, it will be necessary to use two Pendants or a system that has a remote temperature sensor or otherwise provides shade for the temperature sensor and full sunlight for the light sensor.
Some scientist in Switzerland this and told that from the 60's to up to now we got a solar radiation reduction of 15-20%. We should be in an ice time by now but we are not because contrail-cirrus trap infrared radiation from escaping

Note: Mention of commercial products does not imply that they are endorsed by NASA. Analysis Ideas:

Design an experiment to measure the temperature change that occurs when a contrail passes in front of the sun and shades the ground. Related Projects:
I rather concentrate on relative humidity and provide the evidence that we have almost no homogeneous ice nucleation anymore but heterogeneous ice nucleation instead and contrail-cirrus despite to low humidity for contrail-cirrus.

The GLOBE Program.The CERES S’COOL Project. Questions:

1. Are contrails composed of droplets of water or ice crystals? How can you be sure?
Water, soot, metal particles, aluminum, barium, strontium etc.

2. Why are some contrails very short and others very long?

Difference in humidity and composition of the fuel and extra chemicals dispersed to create artificial clouds.

4. When the air where most passenger aircraft fly is moist and cold, would you expect more or fewer contrails? Going Further:
The duration of contrails depend on aerosols and humidity and weather modification chemicals

Learning about contrails will teach you important facts about a man made phenomenon that directly affects the environment in ways that remain to be fully understood.
Yes. I learned plenty about crimes committed by governments and lying scientist whose wages depend on lying for their criminal government.

Serious contrail watchers who want to make a difference should consider participating in S’COOL or GLOBE.
By now more serious scientists use beside the word contrail also words like persistent-contrail, spreading persistent-contrail and contrail-cirrus. This guy looks more like spreading disinfo.

The web has many contrail sites. Enter ‘contrails’ in a search window and prepare to be surprised by the number of sites that appear. Some sites are excellent. But there are also many sites that claim contrails are actually ‘chemtrails’ intended to spread potentially dangerous chemicals or even diseases across cities and the countryside. Some chemtrail sites have excellent photographs of unusual contrail patterns across the sky. Do these sites describe real science? Or do they describe pseudoscience (false science)? How can you tell the difference?
How can you tell the difference?   I know that no liar can remember all his lies and different scientific liars will tell different lies and I assume among all those lies we will also find bits of truth and by making my own observations, using my own tools whereby the main tool is common sense. I use science to debunk lies by scientists whose pay check depend of lying for their corrupt and criminal government.