AS A FORCE MULTIPLIER: OWNING THE WEATHER IN 2025
MILITARY APPLICATIONS OF WEATHER MODIFICATION
4 - Concept of Operations
The essential ingredient of the weather-modification system is
the set of intervention techniques used to modify the weather.
The number of specific intervention methodologies is limited only
by the imagination, but with few exceptions they involve infusing
either energy or chemicals into the meteorological process in
the right way, at the right place and time. The intervention could
be designed to modify the weather in a number of ways, such as
influencing clouds and precipitation, storm intensity, climate,
space, or fog.
For centuries man has desired the ability to influence precipitation
at the time and place of his choosing. Until recently, success
in achieving this goal has been minimal; however, a new window
of opportunity may exist resulting from development of new technologies
and an increasing world interest in relieving water shortages
through precipitation enhancement. Consequently, we advocate that
the DOD explore the many opportunities (and also the ramifications)
resulting from development of a capability to influence precipitation
or conducting "selective precipitation modification." Although
the capability to influence precipitation over the long term (i.e.,
for more than several days) is still not fully understood. By
2025 we will certainly be capable of increasing or decreasing
precipitation over the short term in a localized area.
Before discussing research in this area, it is important to describe
the benefits of such a capability. While many military operations
may be influenced by precipitation, ground mobility is most affected.
Influencing precipitation could prove useful in two ways. First,
enhancing precipitation could decrease the enemy's trafficability
by muddying terrain, while also affecting their morale. Second,
suppressing precipitation could increase friendly trafficability
by drying out an otherwise muddied area.
What is the possibility of developing this capability and applying
it to tactical operations by 2025? Closer than one might think.
Research has been conducted in precipitation modification for
many years, and an aspect of the resulting technology was applied
to operations during the Vietnam War. These initial attempts provide
a foundation for further development of a true capability for
selective precipitation modification.
Interestingly enough, the US government made a conscious decision
to stop building upon this foundation. As mentioned earlier, international
agreements have prevented the US from investigating weather-modification
operations that could have widespread, long-lasting, or severe
effects. However, possibilities do exist (within the boundaries
of established treaties) for using localized precipitation modification
over the short term, with limited and potentially positive results.
These possibilities date back to our own previous experimentation
with precipitation modification. As stated in an article appearing
in the ,Journal of Applied Meteorology,
[n]early all the weather-modification efforts over the last quarter
century have been aimed at producing changes on the cloud scale
through exploitation of the saturated vapor pressure difference
between ice and water. This is not to be criticized but it is
time we also consider the feasibility of weather-modification
on other time-space scales and with other physical hypotheses.20
This study by William M. Gray, et al., investigated the hypothesis
that "significant beneficial influences can be derived through
judicious exploitation of the solar absorption potential of carbon
black dust." The study ultimately found that this technology could
be used to enhance rainfall on the mesoscale, generate cirrus
clouds, and enhance cumulonimbus (thunderstorm) clouds in otherwise
The technology can be described as follows. Just as a black tar
roof easily absorbs solar energy and subsequently radiates heat
during a sunny day, carbon black also readily absorbs solar energy.
When dispersed in microscopic or "dust" form in the air over a
large body of water, the carbon becomes hot and heats the surrounding
air, thereby increasing the amount of evaporation from the body
of water below. As the surrounding air heats up, parcels of air
will rise and the water vapor contained in the rising air parcel
will eventually condense to form clouds. Over time the cloud droplets
increase in size as more and more water vapor condenses, and eventually
they become too large and heavy to stay suspended and will fall
as rain or other forms of precipitation. The study points out
that this precipitation enhancement technology would work best
"upwind from coastlines with onshore flow." Lake-effect snow along
the southern edge of the Great Lakes is a naturally occurring
phenomenon based on similar dynamics.
Can this type of precipitation enhancement technology have military
applications? Yes, if the right conditions exist. For example,
if we are fortunate enough to have a fairly large body of water
available upwind from the targeted battlefield, carbon dust could
be placed in the atmosphere over that water. Assuming the dynamics
are supportive in the atmosphere, the rising saturated air will
eventually form clouds and rainshowers downwind over the land.
While the likelihood of having a body of water located upwind
of the battlefield is unpredictable, the technology could prove
enormously useful under the right conditions. Only further experimentation
will determine to what degree precipitation enhancement can be
If precipitation enhancement techniques are successfully developed
and the right natural conditions also exist, we must also be able
to disperse carbon dust into the desired location. Transporting
it in a completely controlled, safe, cost-effective, and reliable
manner requires innovation. Numerous dispersal techniques have
already been studied, but the most convenient, safe, and cost-effective
method discussed is the use of afterburner-type jet engines to
generate carbon particles while flying through the targeted air.
This method is based on injection of liquid hydrocarbon fuel into
the afterburner's combustion gases. This direct generation method
was found to be more desirable than another plausible method (i.e.,
the transport of large quantities of previously produced and properly
sized carbon dust to the desired altitude).
The carbon dust study demonstrated that small-scale precipitation
enhancement is possible and has been successfully verified under
certain atmospheric conditions. Since the study was conducted,
no known military applications of this technology have been realized.
However, we can postulate how this technology might be used in
the future by examining some of the delivery platforms conceivably
available for effective dispersal of carbon dust or other effective
modification agents in the year 2025.
One method we propose would further maximize the technology's
safety and reliability, by virtually eliminating the human element.
To date, much work has been done on UAVs which can closely (if
not completely) match the capabilities of piloted aircraft. If
this UAV technology were combined with stealth and carbon dust
technologies, the result could be a UAV aircraft invisible to
radar while en route to the targeted area, which could spontaneously
create carbon dust in any location. However, minimizing the number
of UAVs required to complete the mission would depend upon the
development of a new and more efficient system to produce carbon
dust by a follow-on technology to the afterburner-type jet engines
previously mentioned. In order to effectively use stealth technology,
this system must also have the ability to disperse carbon dust
while minimizing (or eliminating) the UAV's infrared heat source.
In addition to using stealth UAV and carbon dust absorption technology
for precipitation enhancement, this delivery method could also
be used for precipitation suppression. Although the previously
mentioned study did not significantly explore the possibility
of cloud seeding for precipitation suppression, this possibility
does exist. If clouds were seeded (using chemical nuclei similar
to those used today or perhaps a more effective agent discovered
through continued research) before their downwind arrival to a
desired location, the result could be a suppression of precipitation.
In other words, precipitation could be "forced" to fall before
its arrival in the desired territory, thereby making the desired
territory "dry." The strategic and operational benefits of doing
this have previously been discussed.
In general, successful fog dissipation requires some type of heating
or seeding process. Which technique works best depends on the
type of fog encountered. In simplest terms, there are two basic
types of fog-cold and warm. Cold fog occurs at temperatures below
32oF. The best-known dissipation technique for cold fog is to
seed it from the air with agents that promote the growth of ice
Warm fog occurs at temperatures above 32oF and accounts for 90
percent of the fog-related problems encountered by flight operations.25
The best-known dissipation technique is heating because a small
temperature increase is usually sufficient to evaporate the fog.
Since heating usually isn't practical, the next most effective
technique is hygroscopic seeding. Hygroscopic seeding uses agents
that absorb water vapor. This technique is most effective when
accomplished from the air but can also be accomplished from the
ground. Optimal results require advance information on fog depth,
liquid water content, and wind.
Decades of research show that fog dissipation is an effective
application of weather-modification technology with demonstrated
savings of huge proportions for both military and civil aviation.
Local municipalities have also shown an interest in applying these
techniques to improve the safety of high-speed highways transiting
areas of frequently occurring dense fog.
There are some emerging technologies which may have important
applications for fog dispersal. As discussed earlier, heating
is the most effective dispersal method for the most commonly occurring
type of fog. Unfortunately, it has proved impractical for most
situations and would be difficult at best for contingency operations.
However, the development of directed radiant energy technologies,
such as microwaves and lasers, could provide new possibilities.
Lab experiments have shown microwaves to be effective for the
heat dissipation of fog. However, results also indicate that the
energy levels required exceed the US large power density exposure
limit of 100 watt/m2 and would be very expensive.31 Field experiments
with lasers have demonstrated the capability to dissipate warm
fog at an airfield with zero visibility. Generating 1 watt/cm2,
which is approximately the US large power density exposure limit,
the system raised visibility to one quarter of a mile in 20 seconds.
Laser systems described in the Space Operations portion of this
AF 2025 study could certainly provide this capability as one of
their many possible uses.
With regard to seeding techniques, improvements in the materials
and delivery methods are not only plausible but likely. Smart
materials based on nanotechnology are currently being developed
with gigaops computer capability at their core. They could adjust
their size to optimal dimensions for a given fog seeding situation
and even make adjustments throughout the process. They might also
enhance their dispersal qualities by adjusting their buoyancy,
by communicating with each other, and by steering themselves within
the fog. They will be able to provide immediate and continuous
effectiveness feedback by integrating with a larger sensor network
and can also change their temperature and polarity to improve
their seeding effects. As mentioned above, UAVs could be used
to deliver and distribute these smart materials.
Recent army research lab experiments have demonstrated the feasibility
of generating fog. They used commercial equipment to generate
thick fog in an area 100 meters long. Further study has shown
fogs to be effective at blocking much of the UV/IR/visible spectrum,
effectively masking emitters of such radiation from IR weapons.34
This technology would enable a small military unit to avoid detection
in the IR spectrum. Fog could be generated to quickly, conceal
the movement of tanks or infantry, or it could conceal military
operations, facilities, or equipment. Such systems may also be
useful in inhibiting observations of sensitive rear-area operations
by electro-optical reconnaissance platforms.
The desirability to modify storms to support military objectives
is the most aggressive and controversial type of weather-modification.
The damage caused by storms is indeed horrendous. For instance,
a tropical storm has an energy equal to 10,000 one-megaton hydrogen
bombs, and in 1992 Hurricane Andrew totally destroyed Homestead
AFB, Florida, caused the evacuation of most military aircraft
in the southeastern US, and resulted in $15.5 billion of damage.
However, as one would expect based on a storm's energy level,
current scientific literature indicates that there are definite
physical limits on mankind's ability to modify storm systems.
By taking this into account along with political, environmental,
economic, legal, and moral considerations, we will confine our
analysis of storms to localized thunderstorms and thus do not
consider major storm systems such as hurricanes or intense low-pressure
At any instant there are approximately 2,000 thunderstorms taking
place. In fact 45,000 thunderstorms, which contain heavy rain,
hail, microbursts, wind shear, and lightning form daily. Anyone
who has flown frequently on commercial aircraft has probably noticed
the extremes that pilots will go to avoid thunderstorms. The danger
of thunderstorms was clearly shown in August 1985 when a jumbo
jet crashed killing 137 people after encountering microburst wind
shears during a rain squall.39 These forces of nature impact all
aircraft and even the most advanced fighters of 1996 make every
attempt to avoid a thunderstorm.
Will bad weather remain an aviation hazard in 2025? The answer,
unfortunately, is "yes," but projected advances in technology
over the next 30 years will diminish the hazard potential. Computer-controlled
flight systems will be able to "autopilot" aircraft through rapidly
changing winds. Aircraft will also have highly accurate, onboard
sensing systems that can instantaneously "map" and automatically
guide the aircraft through the safest portion of a storm cell.
Aircraft are envisioned to have hardened electronics that can
withstand the effects of lightning strikes and may also have the
capability to generate a surrounding electropotential field that
will neutralize or repel lightning strikes.
Assuming that the US achieves some or all of the above outlined
aircraft technical advances and maintains the technological "weather
edge" over its potential adversaries, we can next look at how
we could modify the battlespace weather to make the best use of
our technical advantage.
Weather-modification technologies might involve techniques that
would increase latent heat release in the atmosphere, provide
additional water vapor for cloud cell development, and provide
additional surface and lower atmospheric heating to increase atmospheric
instability. Critical to the success of any attempt to trigger
a storm cell is the pre-existing atmospheric conditions locally
and regionally. The atmosphere must already be conditionally unstable
and the large-scale dynamics must be supportive of vertical cloud
development. The focus of the weather-modification effort would
be to provide additional "conditions" that would make the atmosphere
unstable enough to generate cloud and eventually storm cell development.
The path of storm cells once developed or enhanced is dependent
not only on the mesoscale dynamics of the storm but the regional
and synoptic (global) scale atmospheric wind flow patterns in
the area which are currently not subject to human control.
As indicated, the technical hurdles for storm development in support
of military operations are obviously greater than enhancing precipitation
or dispersing fog as described earlier. One area of storm research
that would significantly benefit military operations is lightning
modification. Most research efforts are being conducted to develop
techniques to lessen the occurrence or hazards associated with
lightning. This is important research for military operations
and resource protection, but some offensive military benefit could
be obtained by doing research on increasing the potential and
intensity of lightning. Concepts to explore include increasing
the basic efficiency of the thunderstorm, stimulating the triggering
mechanism that initiates the bolt, and triggering lightning such
as that which struck Apollo 12 in 1968. Possible mechanisms to
investigate would be ways to modify the electropotential characteristics
over certain targets to induce lightning strikes on the desired
targets as the storm passes over their location.
In summary, the ability to modify battlespace weather through
storm cell triggering or enhancement would allow us to exploit
the technological "weather" advances of our 2025 aircraft; this
area has tremendous potential and should be addressed by future
research and concept development programs.
of "NearSpace" for Space Control
This section discusses opportunities for control and modification
of the ionosphere and near-space environment for force enhancement;
specifically to enhance our own communications, sensing, and navigation
capabilities and/or impair those of our enemy. A brief technical
description of the ionosphere and its importance in current communications
systems is provided in appendix A. By 2025, it may be possible
to modify the ionosphere and near space, creating a variety of
potential applications, as discussed below. However, before ionospheric
modification becomes possible, a number of evolutionary advances
in space weather forecasting and observation are needed. Many
of these needs were described in a Spacecast 2020 study, Space
Weather Support for Communications. Some of the suggestions from
this study are included in appendix B; it is important to note
that our ability to exploit near space via active modification
is dependent on successfully achieving reliable observation and
Afforded by Space Weather-modification
Modification of the near-space environment is crucial to battlespace
dominance. General Charles Horner, former commander in chief,
United States space command, described his worst nightmare as
"seeing an entire Marine battalion wiped out on some foreign landing
zone because he was unable to deny the enemy intelligence and
imagery generated from space."42 Active modification could provide
a "technological fix" to jam the enemy's active and passive surveillance
and reconnaissance systems. In short, an operational capability
to modify the near-space environment would ensure space superiority
in 2025; this capability would allow us to shape and control the
battlespace via enhanced communication, sensing, navigation, and
precision engagement systems.
While we recognize that technological advances may negate the
importance of certain electromagnetic frequencies for US aerospace
forces in 2025 (such as radio frequency (RF), high-frequency (HF)
and very high-frequency (VHF) bands), the capabilities described
below are nevertheless relevant. Our nonpeer adversaries will
most likely still depend on such frequencies for communications,
sensing, and navigation and would thus be extremely vulnerable
to disruption via space weather-modification.
Dominance via Ionospheric Modification
Modification of the ionosphere to enhance or disrupt communications
has recently become the subject of active research. According
to Lewis M. Duncan, and Robert L. Showen, the Former Soviet Union
(FSU) conducted theoretical and experimental research in this
area at a level considerably greater than comparable programs
in the West. There is a strong motivation for this research, because
ionospheric modifications may influence, or even disrupt, the
operation of radio systems relying on propagation through the
modified region. The controlled generation or accelerated dissipation
of ionospheric disturbances may be used to produce new propagation
paths, otherwise unavailable, appropriate for selected RF missions.
A number of methods have been explored or proposed to modify the
ionosphere, including injection of chemical vapors and heating
or charging via electromagnetic radiation or particle beams (such
as ions, neutral particles, x-rays, MeV particles, and energetic
electrons). It is important to note that many techniques to modify
the upper atmosphere have been successfully demonstrated experimentally.
Ground-based modification techniques employed by the FSU include
vertical HF heating, oblique HF heating, microwave heating, and
magnetospheric modification. Significant military applications
of such operations include low frequency (LF) communication production,
HF ducted communications, and creation of an artificial ionosphere
(discussed in detail below). Moreover, developing countries also
recognize the benefit of ionospheric modification: "in the early
1980's, Brazil conducted an experiment to modify the ionosphere
by chemical injection."
Several high-payoff capabilities that could result from the modification
of the ionosphere or near space are described briefly below. It
should be emphasized that this list is not comprehensive; modification
of the ionosphere is an area rich with potential applications
and there are also likely spin-off applications that have yet
to be envisioned.
mirrors for pinpoint communication or over-the-horizon (OTH) radar
transmission. The properties and limitations of the ionosphere
as a reflecting medium for high-frequency radiation are described
in appendix A. The major disadvantage in depending on the ionosphere
to reflect radio waves is its variability, which is due to normal
space weather and events such as solar flares and geomagnetic
storms. The ionosphere has been described as a crinkled sheet
of wax paper whose relative position rises and sinks depending
on weather conditions. The surface topography of the crinkled
paper also constantly changes, leading to variability in its reflective,
refractive, and transmissive properties.
Creation of an artificial uniform ionosphere was first proposed
by Soviet researcher A. V. Gurevich in the mid-1970s. An artificial
ionospheric mirror (AIM) would serve as a precise mirror for electromagnetic
radiation of a selected frequency or a range of frequencies. It
would thereby be useful for both pinpoint control of friendly
communications and interception of enemy transmissions.
This concept has been described in detail by Paul A. Kossey, et
al. in a paper entitled "Artificial Ionospheric Mirrors (AIM)."
The authors describe how one could precisely control the location
and height of the region of artificially produced ionization using
crossed microwave (MW) beams, which produce atmospheric breakdown
(ionization) of neutral species. The implications of such control
are enormous: one would no longer be subject to the vagaries of
the natural ionosphere but would instead have direct control of
the propagation environment. Ideally, the AIM could be rapidly
created and then would be maintained only for a brief operational
period. A schematic depicting the crossed-beam approach for generation
of an AIM is shown in figure 4-1.
An AIM could theoretically reflect radio waves with frequencies
up to 2 GHz, which is nearly two orders of magnitude higher than
those waves reflected by the natural ionosphere. The MW radiator
power requirements for such a system are roughly an order of magnitude
greater than 1992 state-of-the-art systems; however, by 2025 such
a power capability is expected to be easily achievable.
Figure 4-1. Crossed-Beam Approach for Generating an Artificial
Besides providing pinpoint communication control and potential
interception capability, this technology would also provide communication
capability at specified frequencies, as desired. Figure 4-2 shows
how a ground-based radiator might generate a series of AIMs, each
of which would be tailored to reflect a selected transmission
frequency. Such an arrangement would greatly expand the available
bandwidth for communications and also eliminate the problem of
interference and crosstalk (by allowing one to use the requisite
Figure 4-2. Artificial Ionospheric Mirrors Point-to-Point Communications
Kossey et al. also describe how AIMs could be used to improve
the capability of OTH radar:
AIM based radar could be operated at a frequency chosen to optimize
target detection, rather than be limited by prevailing ionospheric
conditions. This, combined with the possibility of controlling
the radar's wave polarization to mitigate clutter effects, could
result in reliable detection of cruise missiles and other low
A schematic depicting this concept is shown in figure 4-3. Potential
advantages over conventional OTH radars include frequency control,
mitigation of auroral effects, short range operation, and detection
of a smaller cross-section target.
Figure 4-3. Artificial Ionospheric Mirror Over-the-Horizon Surveillance
of communications and radar via ionospheric control. A variation
of the capability proposed above is ionospheric modification to
disrupt an enemy's communication or radar transmissions. Because
HF communications are controlled directly by the ionosphere's
properties, an artificially created ionization region could conceivably
disrupt an enemy's electromagnetic transmissions. Even in the
absence of an artificial ionization patch, high-frequency modification
produces large-scale ionospheric variations which alter HF propagation
characteristics. The payoff of research aimed at understanding
how to control these variations could be high as both HF communication
enhancement and degradation are possible. Offensive interference
of this kind would likely be indistinguishable from naturally
occurring space weather. This capability could also be employed
to precisely locate the source of enemy electromagnetic transmissions.
VHF, UHF, and super-high frequency (SHF) satellite communications
could be disrupted by creating artificial ionospheric scintillation.
This phenomenon causes fluctuations in the phase and amplitude
of radio waves over a very wide band (30 MHz to 30 GHz). HF modification
produces electron density irregularities that cause scintillation
over a wide-range of frequencies. The size of the irregularities
determines which frequency band will be affected. Understanding
how to control the spectrum of the artificial irregularities generated
in the HF modification process should be a primary goal of research
in this area. Additionally, it may be possible to suppress the
growth of natural irregularities resulting in reduced levels of
natural scintillation. Creating artificial scintillation would
allow us to disrupt satellite transmissions over selected regions.
Like the HF disruption described above, such actions would likely
be indistinguishable from naturally occurring environmental events.
Figure 4-4 shows how artificially ionized regions might be used
to disrupt HF communications via attenuation, scatter, or absorption
(fig. 4.4a) or degrade satellite communications via scintillation
or energy loss (fig. 4-4b).
Figure 4-4 (a) and (b). Scenarios for Telecommunications Degradation
space assets traversing near-space. The ionosphere could potentially
be artificially charged or injected with radiation at a certain
point so that it becomes inhospitable to satellites or other space
structures. The result could range from temporarily disabling
the target to its complete destruction via an induced explosion.
Of course, effectively employing such a capability depends on
the ability to apply it selectively to chosen regions in space.
space assets by near-space energy transfer. In contrast to
the injurious capability described above, regions of the ionosphere
could potentially be modified or used as-is to revitalize space
assets, for instance by charging their power systems. The natural
charge of the ionosphere may serve to provide most or all of the
energy input to the satellite. There have been a number of papers
in the last decade on electrical charging of space vehicles; however,
according to one author, "in spite of the significant effort made
in the field both theoretically and experimentally, the vehicle
charging problem is far from being completely understood." While
the technical challenge is considerable, the potential to harness
electrostatic energy to fuel the satellite's power cells would
have a high payoff, enabling service life extension of space assets
at a relatively low cost. Additionally, exploiting the capability
of powerful HF radio waves to accelerate electrons to relatively
high energies may also facilitate the degradation of enemy space
assets through directed bombardment with the HF-induced electron
beams. As with artificial HF communication disruptions and induced
scintillation, the degradation of enemy spacecraft with such techniques
would be effectively indistinguishable from natural environment
effects. The investigation and optimization of HF acceleration
mechanisms for both friendly and hostile purposes is an important
area for future research efforts.
While most weather-modification efforts rely on the existence
of certain preexisting conditions, it may be possible to produce
some weather effects artificially, regardless of preexisting conditions.
For instance, virtual weather could be created by influencing
the weather information received by an end user. Their perception
of parameter values or images from global or local meteorological
information systems would differ from reality. This difference
in perception would lead the end user to make degraded operational
Nanotechnology also offers possibilities for creating simulated
weather. A cloud, or several clouds, of microscopic computer particles,
all communicating with each other and with a larger control system
could provide tremendous capability. Interconnected, atmospherically
buoyant, and having navigation capability in three dimensions,
such clouds could be designed to have a wide-range of properties.
They might exclusively block optical sensors or could adjust to
become impermeable to other surveillance methods. They could also
provide an atmospheric electrical potential difference, which
otherwise might not exist, to achieve precisely aimed and timed
lightning strikes. Even if power levels achieved were insufficient
to be an effective strike weapon, the potential for psychological
operations in many situations could be fantastic.
One major advantage of using simulated weather to achieve a desired
effect is that unlike other approaches, it makes what are otherwise
the results of deliberate actions appear to be the consequences
of natural weather phenomena. In addition, it is potentially relatively
inexpensive to do. According to J. Storrs Hall, a scientist at
Rutgers University conducting research on nanotechnology, production
costs of these nanoparticles could be about the same price per
pound as potatoes. This of course discounts research and development
costs, which will be primarily borne by the private sector and
be considered a sunk cost by 2025 and probably earlier.
of Operations Summary
Weather affects everything we do, and weather-modification can
enhance our ability to dominate the aerospace environment. It
gives the commander tools to shape the battlespace. It gives the
logistician tools to optimize the process. It gives the warriors
in the cockpit an operating environment literally crafted to their
needs. Some of the potential capabilities a weather-modification
system could provide to a war-fighting CINC are summarized in
table 1, of the executive summary).
- Page 1 - Page
2 - Page 3 - Page 4 - Page
5 - Appendix